0001437749-23-005222 | 10-K | XBRL Viewer

Lessee, Operating Leases [Text Block]

10.

Leases

Lessee Information

Components of operating lease expense are primarily recorded in general and administrative on the consolidated statements of operations and comprehensive loss were as follows:

	Years Ended December 31,
	2022		2021
	(in thousands)
Long-term Operating	$	1,557	$	1,826
Short-term Operating		-		-
Total Operating lease expense	$	1,557	$	1,826

Supplemental balance sheet information related to operating leases was as follows:

	December 31, 2022			December 31, 2021
Weighted-average remaining lease term (in years)	6.8			7.8
Weighted-average discount rate	8.4%			7.8%
Incremental borrowing rate	6.1%	-	14.5%	6.1%	-	8.5%

Maturities of operating lease obligations as of December 31, 2022 were as follows (in thousands):

Fiscal Year
2023	$	1,222
2024		1,136
2025		1,058
2026		837
2027		775
Thereafter		2,195
Total minimum lease payments	$	7,223
Less: Amount of lease payments representing interest		(1,685	)
Present value of future minimum lease payments	$	5,538

Significant Accounting Policies (Policies)

12 Months Ended

Dec. 31, 2022

Accounting Policies [Abstract]

Basis of Accounting, Policy [Policy Text Block]

Basis of Presentation

Substantial Doubt about Going Concern [Policy Text Block]

Going Concern

The Company's consolidated financial statements are prepared using U.S. GAAP applicable to a going concern, which contemplate the realization of assets and liquidation of liabilities in the normal course of business. The Company had an accumulated deficit of $860.9 million and working capital of $76.5 million as of December 31, 2022. The Company has not established sufficient sales revenues to cover its operating costs and requires additional capital to proceed with its operating plan. The ability of the Company to continue as a going concern is dependent on the Company obtaining adequate capital to fund operating losses until it becomes profitable.

The Company will need to obtain additional financing to proceed with its business plan. Management's plan to obtain additional resources for the Company may include additional sales of equity, traditional financing, such as loans, entry into a strategic collaboration, entry into an out-licensing arrangement or provision of additional distribution rights in some or all of our markets. However, management cannot provide any assurance that the Company will be successful in accomplishing any or all of its plans. The ability to successfully resolve these factors raise substantial doubt about the Company’s ability to meet its existing obligations, and to continue as a going concern within one year from the date that these financial statements are issued. The consolidated financial statements of the Company do not include any adjustments that may result from the outcome of these aforementioned uncertainties.

Consolidation, Policy [Policy Text Block]

Principles of Consolidation and Foreign Currency Considerations

The accompanying consolidated financial statements include the accounts of the Company and its direct and indirect wholly owned subsidiaries, Asensus Surgical US, Inc., Asensus International, Inc., Asensus Surgical Italia S.r.l., Asensus Surgical Europe S.à r.l., Asensus Surgical Taiwan Ltd., Asensus Surgical Japan K.K., Asensus Surgical Israel Ltd., Asensus Surgical Netherlands B.V., and Asensus Surgical Canada, Inc. All inter-company accounts and transactions have been eliminated in consolidation.

The functional currency of the Company’s operational foreign subsidiaries is predominantly the Euro. The assets and liabilities of the Company’s foreign subsidiaries are translated into U.S. dollars at exchange rates in effect at the balance sheet date. Income and expense items are translated at the average exchange rates prevailing during the period. The cumulative translation effect for a subsidiary using a functional currency other than the U.S. dollar is included in accumulated other comprehensive loss as a separate component of stockholders’ equity.

The Company’s intercompany accounts are denominated in the functional currency of the foreign subsidiary. Gains and losses resulting from the remeasurement of intercompany receivables that the Company considers to be of a long-term investment nature are recorded as a cumulative translation adjustment in accumulated other comprehensive loss as a separate component of stockholders’ equity, while gains and losses resulting from the remeasurement of intercompany receivables from a foreign subsidiary for which the Company anticipates settlement in the foreseeable future are recorded in the consolidated statements of operations and comprehensive loss. The net gains and losses included in net loss in the consolidated statements of operations and comprehensive loss for the years ended December 31, 2022 and 2021 were not material.

Reclassification, Comparability Adjustment [Policy Text Block]

Reclassifications

Certain amounts reported previously have been reclassified to conform to the current year presentation, with no effect on stockholders’ equity or net loss as previously reported. Revenue and cost of revenue for leases were historically included in product and service revenue and corresponding cost of revenue on the consolidated statements of operations and comprehensive loss for the year ended December 31, 2021. Accrued employee compensation and benefits were historically included in accrued expenses and other current liabilities on the consolidated balance sheets for the year ended December 31, 2021.

Error Correction and Revisions [Policy Text Block]

Revision of Previously Disclosed Amounts

During the course of preparing the Company’s unaudited consolidated financial statements as of and for the six months ended June 30, 2022, the Company determined that its December 31, 2021 inventory footnote presentation overstated raw materials and understated finished goods by $2.5 million. For comparative purposes, Note 7 – Inventories, has been revised to reflect the adjustment to raw materials and finished goods as of December 31, 2021. The revision had no effect on the previously reported total gross and net carrying value of inventory. The revision also had no effect on the previously reported consolidated balance sheets, statements of operations and comprehensive loss, cash flows and stockholders’ equity.

Risk And Uncertainties, Policy [Policy Text Block]

Risk and Uncertainties

The Company is subject to risks similar to other similarly sized companies in the medical device industry. These risks include, without limitation: negative impacts on the Company's operations caused by the COVID-19 pandemic and other geopolitical factors; the historical lack of profitability; the Company’s ability to raise additional capital; the success of its market development efforts; its ability to successfully develop, clinically test and commercialize its products; the timing and outcome of the regulatory review process for its products; changes in the healthcare regulatory environments of the United States, the European Union, Japan, Taiwan, and other countries in which the Company operates or intends to operate; its ability to attract and retain key management, marketing and scientific personnel; its ability to successfully prepare, file, prosecute, maintain, defend and enforce patent claims and other intellectual property rights; its ability to successfully transition from a research and development company to a marketing, sales and distribution company; competition in the market for robotic surgical devices; and its ability to identify and pursue development of additional products.

Use of Estimates, Policy [Policy Text Block]

Use of Estimates

The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates. Significant items subject to such estimates and assumptions include impairment considerations for long-lived assets, fair value estimates related to contingent consideration, stock compensation expense, revenue recognition, short-term and long-term investments, excess and obsolete inventory reserves, inventory classification between current and non-current, measurement of lease liabilities and corresponding right-of-use (“ROU”) assets, and deferred tax asset valuation allowances.

Cash and Cash Equivalents, Restricted Cash, and Investments, Policy [Policy Text Block]

Cash and Cash Equivalents, Restricted Cash, and Investments

The Company considers all highly liquid investments with original maturities of 90 days or less at the time of purchase to be cash equivalents.

Restricted cash as of December 31, 2022 and 2021 includes $1.1 million in cash accounts held as collateral primarily under the terms of an office operating lease, credit cards, and automobile leases.

The Company’s investments as of December 31, 2022 consisted of commercial paper, corporate bonds, and United States government agencies and were classified as available-for-sale. Investments classified as available-for-sale are measured at fair value, and net unrealized gains and losses are recorded as a component of accumulated other comprehensive loss on the consolidated balance sheets until realized. The amortized cost of debt securities is adjusted for amortization of premiums and accretion of discounts to maturity computed under the effective interest method. Such amortization and accretion is included in interest expense, net. There were no gross realized gains or loss for the year ended December 31, 2022. The Company recognized an immaterial amount of gross realized losses for the year ended December 31, 2021. There were no gross realized gains for the year ended December 31, 2021.

Investments with remaining maturities at date of purchase greater than 90 days and remaining maturities as of the reporting period less than one year are classified as short-term investments. Investments with remaining maturities greater than one year are classified as long-term investments.

There have been no credit losses for the years ended December 31, 2022 and 2021, and no allowance for credit losses as of December 31, 2022. Factors considered in determining whether a credit loss exists include credit ratings and other qualitative factors for each security type in the portfolio.

Fair Value Measurement, Policy [Policy Text Block]

Fair Value Measurements

The Company measures the fair value of money market funds, certain U.S. treasury securities, and equity investments with readily determinable value based on quoted prices in active markets for identical assets as Level 1 securities. Marketable securities measured at fair value using Level 2 inputs are primarily comprised of commercial paper and corporate notes and bonds without readily determinable value. The Company reviews trading activity and pricing for these investments as of the measurement date. When sufficient quoted pricing for identical securities is not available, the Company uses market pricing and other observable market inputs for similar securities obtained from various third-party data providers. These inputs either represent quoted prices for similar assets in active markets or have been derived from observable market data. This approach results in the Level 2 classification of these securities within the fair value hierarchy. The Company measures contingent consideration at fair value using a Monte-Carlo simulation utilizing Level 3 inputs. These inputs include the probability of achieving each of the potential milestones, revenue volatility, and an estimated discount rate associated with the risks of the expected cash flows attributable to the achievement of various milestones.

Concentration Risk, Credit Risk, Policy [Policy Text Block]

Concentrations and Credit Risk

The Company’s principal financial instruments subject to potential concentration of credit risk are cash and cash equivalents (including restricted cash), and investments, including amounts held in money market funds, commercial paper, and corporate bonds. The Company places cash deposits with a federally insured financial institution. The Company maintains its cash at banks and financial institutions it considers to be of high credit quality; however, the Company’s domestic cash deposits may at times exceed the Federal Deposit Insurance Corporation’s insured limit. Balances in excess of federally insured limitations may not be insured. The Company has not experienced losses on these accounts, and management believes that the Company is not exposed to significant risks on such accounts. Investments are stated at their estimated fair values, based on quoted market prices for the same or similar instruments. The counterparties to the agreements relating to the Company’s investments consist of various major corporations, financial institutions, and government agencies of high credit standing.

The Company’s accounts receivable are derived from sales and leases to customers located throughout the world. The Company evaluates its customers’ financial condition and, generally, requires no collateral from its customers. The Company had one customer that accounted for 69% of the Company’s net accounts receivable as of December 31, 2022. The Company had three customers that accounted for 26%, 20%, and 14%, respectively, of the Company’s net accounts receivable as of December 31, 2021. The Company had one customer who accounted for 47% of revenue in 2022, and two customers who accounted for 36% and 16% of revenue in 2021, respectively.

Receivable [Policy Text Block]

Accounts Receivable

Accounts receivable are recorded at net realizable value, which includes an allowance for expected credit losses. The allowance for expected credit losses is based on the Company’s assessment of collectability of customer accounts. The Company regularly reviews the allowance by considering factors such as historical experience, credit quality, the age of the accounts receivable balances, and current economic conditions that may affect a customer’s ability to pay. The allowance for expected credit losses was $1.6 million and $1.7 million as of December 31, 2022, and December 31, 2021, respectively. The Company recorded an immaterial amount for expected credit losses during the year ended December 31, 2022 and $0.1 million during the year ended December 31, 2021.

Inventory, Policy [Policy Text Block]

Inventories

Inventories are stated at the lower of cost (determined on a first-in, first-out basis) or net realizable value. Inventory costs include direct materials, direct labor, and normal manufacturing overhead. The Company records reserves, when necessary, to reduce the carrying value of inventory to its net realizable value. Management considers historical consumption and forecast demand in relation to the inventory on hand, competitiveness of product offerings, market conditions and product life cycles when determining excess and obsolescence and net realizable value adjustments. At the point of loss recognition, a new, lower-cost basis for that inventory is established, and any subsequent improvements in facts and circumstances do not result in the restoration or increase in that newly established cost basis.

Any inventory on hand at the measurement date in excess of the Company's current requirements based on anticipated levels of sales is classified as long-term on the Company's consolidated balance sheets. The Company's classification of long-term inventory requires it to estimate the portion of on hand inventory that can be realized over the upcoming twelve months.

Goodwill and Intangible Assets, Policy [Policy Text Block]

Definite-Lived Intangible Assets - Intellectual Property

Intellectual property consists of purchased patent rights and developed technology acquired as part of a business acquisition. Developed technology includes reclassified in-process research and development (“IPR&D”) assets related to (i) the Senhance System acquired in 2015 and reclassified in 2017 and (ii) a 2018 acquisition and reclassified in 2020. Amortization of the patent rights is recorded using the straight-line method over the estimated useful life of the patents of 10 years. Amortization of the developed technology is recorded using the straight-line method over the estimated useful life of 5 to 7 years.

The Company periodically evaluates intellectual property for impairment whenever events or changes in circumstances indicate that the carrying amount may not be recoverable. To determine the recoverability, the Company evaluates the probability that future estimated undiscounted net cash flows will be less than the carrying amount of the assets. If such estimated cash flows are less than the carrying amount of the assets, then such assets are written down to their fair value. No impairment of intellectual property was identified during the years ended December 31, 2022 and 2021.

Property, Plant and Equipment, Policy [Policy Text Block]

Property and Equipment

Property and equipment consists primarily of operating lease Senhance System assets, machinery, manufacturing equipment, demonstration equipment, computer equipment, furniture, and leasehold improvements, which are recorded at cost less accumulated depreciation. Depreciation is recorded using the straight-line method over the estimated useful lives of the assets as follows:

The Company reviews its property and equipment assets for possible impairment whenever events or changes in circumstances indicate that the carrying amount of the assets may not be fully recoverable. To determine the recoverability of its long-lived assets, the Company evaluates the probability that future estimated undiscounted net cash flows will be less than the carrying amount of the assets. If such estimated cash flows are less than the carrying amount of the long-lived assets, then such assets are written down to their fair value.

During the year ended December 31, 2022, the Company recorded a non-cash asset impairment charge of $1.4 million to reduce the carrying value of property and equipment to its estimated fair value. The property and equipment impairment is associated with returned Senhance Systems under operating leases and Senhance Systems currently under operating leases that are not expected to generate future cash flows sufficient to recover their net book value. The fair value was estimated based on the discounted cash flows expected to be produced by the property and equipment. The impairment was recorded in property and equipment impairment on the consolidated statements of operations and comprehensive loss. No such impairment charges were recorded during the year ended December 31, 2021.

Lessee, Leases [Policy Text Block]

Operating Leases

We have operating leases for our corporate office buildings, vehicles, and machinery and equipment. At inception, we determine whether an agreement represents a lease and, at commencement, we evaluate each lease agreement to determine whether the lease constitutes an operating or financing lease.

The Company accounts for lease components and non-lease components as a single component. Non-lease components consist of common area maintenance payments for most real estate leases, which are determined based on costs incurred by the lessor. Many of the Company’s leases include base rental periods coupled with options to renew or terminate the lease, generally at the Company’s discretion. In evaluating the lease term, the Company considers whether renewal is reasonably certain. To the extent a significant economic incentive exists to renew the lease, the option is included within the lease term. Based on the Company’s leases, renewal options generally do not provide a significant economic incentive and are therefore excluded from the lease term. While our operating leases range from one year to ten years, some may include options to extend the lease generally between one year and six years, and some may include options to terminate the leases within one year.

The interest rate implicit in our lease contracts is typically not readily determinable. As such, we utilize the appropriate incremental borrowing rate, which is the rate incurred to borrow on a collateralized basis over a similar term an amount equal to the lease payments in a similar economic environment. Operating lease expense is recognized on a straight-line basis over the lease term, subject to any changes in the lease or expectations regarding the terms.

Capitalization of Internal Costs, Policy [Policy Text Block]

Implementation Costs in a Cloud Computing Arrangement

The Company capitalizes qualified implementation costs incurred in a hosting arrangement that is a service contract. These capitalized implementation costs are recorded within other current and long-term assets, and are generally amortized over the fixed, non-cancellable term of the associated hosting arrangement on a straight-line basis and included within operating expenses.

Employer Retention Tax Credit, Policy [Policy Text Block]

Employee Retention Tax Credit Receivable

The Coronavirus Aid, Relief, and Economic Security Act (the “CARES Act”) included an Employee Retention Tax Credit (“ERTC”) provision designed to encourage employers to keep employees on their payroll. The ERTC is a refundable tax credit against certain payroll taxes paid by employers for eligible wages. During the year ended December 31, 2021, we submitted an ERTC refund for $1.3 million and recorded the amount into Other Income (Expense) on the consolidated statements of operations and comprehensive loss. The Company received notification from the IRS that the relevant conditions of the employee retention credit provision were met and that it will receive the credit. The Company received $0.7 million of the ERTC refund during the year ended December 31, 2022. The remaining $0.6 million is recorded as a current asset on the consolidated balance sheets as of December 31, 2022.

Debt, Policy [Policy Text Block]

Notes Payable

The Company’s policy is to account for forgivable loans received through the U.S. Small Business Administration (the “SBA”) under the CARES Act Payroll Protection Program (“PPP”), as debt in accordance with ASC 470, Debt, and other related accounting pronouncements. The forgiveness of debt, in whole or part, is recognized once the debt is extinguished, which occurs when the Company is legally released from the liability by the SBA. Any portion of debt forgiven, adjusted for accrued interest forgiven and unamortized debt issuance costs, is recorded as a gain on extinguishment of debt, and presented in the consolidated statements of operations and comprehensive loss. On June 10, 2021, the Company received notification from the SBA that the principal amount of its PPP loan of $2.8 million and related interest had been forgiven.

As of December 31, 2022, the Company has $0.6 million available under a letter of credit. No amounts have been utilized by the Company as of December 31, 2022.

Contingent Consideration [Policy Text Block]

Contingent Consideration

Contingent consideration is recorded as a liability and is the estimate of the fair value of potential milestone payments related to business acquisitions. Contingent consideration is measured at fair value using a Monte-Carlo simulation utilizing significant unobservable inputs including the probability of achieving each of the potential milestones, future Euro-to-USD exchange rates, revenue volatility and an estimated discount rate associated with the risks of the expected cash flows attributable to the various milestones. Significant increases or decreases in any of the probabilities of success or changes in expected achievement of any of these milestones would result in a significantly higher or lower fair value of these milestones, respectively, and commensurate changes to the associated liability. The contingent consideration is revalued at each reporting period and changes in fair value are recognized in the consolidated statements of operations and comprehensive loss.

On September 21, 2015, the Company completed the strategic acquisition, through its wholly owned subsidiary TransEnterix International, from Sofar S.p.A., an Italian company (“Sofar”), an Italian company, of all of the assets, employees and contracts related to the advanced robotic system for minimally invasive laparoscopic surgery now known as the Senhance System. Under the terms of the Purchase Agreement, as amended in 2016, as of December 31, 2022, the Company has accrued $1.3 million of estimated fair value of remaining contingent consideration related to a milestone of €15.0 million which shall be payable upon achievement of trailing revenues from sales or services contracts of the Senhance System of at least €25.0 million over a calendar quarter or in the event that (i) the Company or Asensus International is acquired, (ii) the Company significantly reduces or suspends selling efforts of the Senhance System, or (iii) the Company acquires a business that offers alternative products that are directly competitive with the Senhance System. In 2022, Sofar assigned its right to receive the contingent payment to Three Heads Investment S.r.l.

Warrant Liabilities [Policy Text Block]

Warrant Liabilities

The Company’s Series B Warrants were measured at fair value using a simulation model which considered, as of the valuation date, factors including the current exercise price, the expected life of the warrant, the current price of the underlying stock, its expected volatility, holding cost and the risk-free interest rate for the term of the warrant. The warrant liability was revalued at each reporting period and changes in fair value were recognized in the consolidated statements of operations and comprehensive loss. The selection of the appropriate valuation model and the inputs and assumptions that are required to determine the valuation requires significant judgment and requires management to make estimates and assumptions that affect the reported amount of the related liability and reported amounts of the change in fair value. Actual results could differ from those estimates, and changes in these estimates are recorded when known. All remaining outstanding Series B Warrants were exercised in the first quarter 2021.

Revenue [Policy Text Block]

Revenue Recognition

The Company’s revenue consists of product revenue resulting from the sale of Senhance Systems, Senhance System components, and instruments and accessories. Service revenue consists of revenue related to Senhance System service agreements. Lease revenue consists of revenue generated from utilizing the Senhance System, instruments and accessories, and servicing of the Senhance System under operating lease agreements. The Company accounts for a contract with a customer when there is a legally enforceable contract between the Company and the customer, the rights of the parties are identified, the contract has commercial substance, and collectability of the contract consideration is probable. The Company's revenues are measured based on consideration specified in the contract with each customer, net of any sales incentives and taxes collected from customers that are remitted to government authorities. The Company’s Senhance System sale arrangements generally include a five-year service period; the first year of service is generally free and included in the Senhance System sale arrangement and the remaining four years are generally included at a stated service price.

The Company’s Senhance System sale arrangements generally contain multiple products and services. For these consolidated sale arrangements, the Company accounts for individual products and services as separate performance obligations if they are distinct, which is if a product or service is separately identifiable from other items in the consolidated package, and if a customer can benefit from it on its own or with other resources that are readily available to the customer. The Company’s Senhance System sale arrangements may include a combination of the following performance obligations: system(s), system components, instruments, accessories, and system services.

For arrangements that contain multiple performance obligations, revenue is allocated to each performance obligation based on its relative estimated standalone selling price. When available, standalone selling prices are based on observable prices at which the Company separately sells the products or services; however due to limited sales to date, standalone selling prices generally are not directly observable. The Company estimates the standalone selling price using the market assessment approach considering market conditions and entity-specific factors including, but not limited to, features and functionality of the products and services, geographies, type of customer, and market conditions. The Company regularly reviews estimated standalone selling prices and updates these estimates if necessary.

The Company recognizes revenues when or as the performance obligations are satisfied by transferring control of the product or service to a customer. The Company generally recognizes revenue for the performance obligations as follows:

• System sales. For Senhance Systems and Senhance System components sold directly to end customers (including those arising from Senhance System purchases under lease rights to purchase), revenue is recognized when the Company transfers control to the customer, which is generally at the point when acceptance occurs that indicates customer acknowledgment of delivery or installation, depending on the terms of the arrangement. For lease buyouts, where the customer has already acknowledged installation of the system, transfer of control occurs when the Company receives an executed contract for the lease buyout of the Senhance System. For Senhance Systems sold through distributors, for which distributors are responsible for installation, revenue is recognized generally upon delivery. The Company’s Senhance System arrangements generally do not provide a right of return. The Senhance Systems are generally covered by a one-year warranty. Warranty costs were not material for the periods presented.

• Instruments and accessories. Revenue from sales of instruments and accessories is recognized when control is transferred to the customers, which generally occurs at the time of shipment, but also occurs at the time of delivery depending on the customer arrangement.

• Service. Service revenue is recognized ratably over the term of the service period as the customers benefit from the service throughout the service period. Revenue related to services performed on a time-and-materials basis is recognized when performed.

The Company invoices its customers based on the billing schedules in its sales arrangements. Payments are generally due 30 to 60 days from the date of invoice. Contract assets for the periods presented primarily represent the difference between the revenue that was recognized based on the relative selling price of the related performance obligations and the contractual billing terms in the arrangements, and are included in accounts receivable.

In connection with assets recognized from the costs to obtain a contract with a customer, the Company determined that the sales incentive programs for its sales team do not meet the requirements to be capitalized as the Company does not expect to generate future economic benefits from the related revenue from the initial sales transaction and such costs are expensed as incurred.

Lessor, Leases [Policy Text Block]

Senhance System Leasing

The Company enters into lease arrangements with certain qualified customers. Revenue related to arrangements including lease elements are allocated to lease and non-lease elements based on their relative standalone selling prices. Lease elements generally include a Senhance System, while non-lease elements generally include instruments, accessories, and services. For some lease arrangements, the customers are provided with the right to purchase the leased Senhance System at some point during and/or at the end of the lease term. In some arrangements lease payments are based on the usage of the Senhance System. For the years ended December 31, 2022 and 2021, variable lease revenue related to usage-based arrangements was not material.

In determining whether a transaction should be classified as a sales-type, operating, or direct financing lease, the Company considers the following terms at lease commencement: (1) whether title of the Senhance System transfers automatically or for a nominal fee by the end of the lease term, (2) whether the present value of the minimum lease payments equals or exceeds substantially all of the fair value of the leased Senhance System, (3) whether the lease term is for the major part of the remaining economic life of the leased System, (4) whether the lease grants the lessee an option to purchase the leased Senhance System that the lessee is reasonably certain to exercise, and (5) whether the underlying Senhance System is of such a specialized nature that it is expected to have no alternative use to the Company at the end of the lease term. All such arrangements through December 31, 2022 are classified as operating leases. Revenue related to lease elements from operating lease arrangements is generally recognized on a straight-line basis over the lease term or based upon Senhance System usage. As of December 31, 2022 future minimum lease payments due from customers was $2.2 million, which is expected to be received over the next one to three years.

Cost of Goods and Service [Policy Text Block]

Cost of Revenue

Cost of revenue consists of contract manufacturing, materials, labor and manufacturing overhead incurred internally to produce the products. Depreciation expense related to leased systems is included in the cost of revenue. Shipping and handling costs incurred by the Company are included in the cost of revenue. We expense all inventory obsolescence provisions as cost of revenue.

Research and Development Expense, Policy [Policy Text Block]

Research and Development Costs

Research and development expenses primarily consist of engineering, product development and regulatory expenses, incurred in the design, development, testing and enhancement of our products. Research and development costs are expensed as incurred.

Share-Based Payment Arrangement [Policy Text Block]

Stock-Based Compensation

The Company recognizes expenses for share-based awards exchanged for services rendered equal to the estimated fair value of these awards over the requisite service period. The Company recognizes as expense, the grant-date fair value of stock options and other stock-based compensation issued to employees and non-employee directors over the requisite service periods, which are typically the vesting periods. The Company uses the Black-Scholes-Merton model to estimate the fair value of stock options. The volatility assumption used in the Black-Scholes-Merton model is based on the Company’s historical volatility. The expected term of options granted has been determined based upon the simplified method, because the Company does not have sufficient historical information regarding its options to derive the expected term. Under this approach, the expected term is the mid-point between the weighted average of vesting period and the contractual term. The risk-free interest rate is based on U.S. Treasury rates whose term is consistent with the expected life of the stock options. The Company has not paid and does not anticipate paying cash dividends on its shares of common stock; therefore, the expected dividend yield is assumed to be zero. The Company estimates forfeitures based on its historical experience and adjust the estimated forfeiture rate based upon actual experience. For performance-based restricted stock awards with performance conditions, we begin recognizing compensation expense when it becomes probable that the performance condition will be attained.

The fair value of restricted stock units is determined by the market price of the Company’s common stock on the date of grant. See “Note 13 – Stock-Based Compensation,” for a detailed discussion of the Company’s stock plans and stock-based compensation expense.

Income Tax, Policy [Policy Text Block]

Income Taxes

The Company accounts for income taxes using the asset and liability method, which requires the recognition of deferred tax assets or liabilities for the temporary differences between financial reporting and tax basis of the Company’s assets and liabilities, and for tax carryforwards at enacted statutory rates in effect for the years in which the asset or liability is expected to be realized. The effect on deferred taxes of a change in tax rates is recognized in income during the period that includes the enactment date. In addition, valuation allowances are established when necessary to reduce deferred tax assets and liabilities to the amounts expected to be realized. The Company has elected to account for global intangible low-taxed income (“GILTI”) as a period expense in the year the tax is incurred.

The Company recognizes the financial statement benefit of an income tax position only after determining that the relevant taxing authority would more likely than not sustain the position following audit. For tax positions meeting the more likely than not threshold, the amount recognized in the financial statements is the largest benefit that has a greater than 50% likelihood of being realized upon ultimate settlement with the relevant taxing authority. The Company recognizes interest accrued related to unrecognized tax benefits and penalties in the provision for income taxes.

Tax regulations within each jurisdiction are subject to the interpretation of the related tax laws and regulations and require application of significant judgment. The Company is subject to U.S. federal and various state, local and foreign jurisdictions. Due to the Company’s net operating loss carryforwards, the Company may be subject to examination by authorities for all previously filed income tax returns.

Comprehensive Income, Policy [Policy Text Block]

Comprehensive Loss

Comprehensive loss is defined as the change in equity of a business enterprise during a period from transactions and other events and circumstances from non-owner sources.

Segment Reporting, Policy [Policy Text Block]

Segments

The Company operates in one business segment—the research, development and sale of medical device robotics to improve minimally invasive surgery. The Company’s chief operating decision maker (determined to be the Chief Executive Officer) does not manage any part of the Company separately, and the allocation of resources and assessment of performance are based on the Company’s consolidated operating results.

New Accounting Pronouncements, Policy [Policy Text Block]

Impact of Recently Issued Accounting Standards

The Company has evaluated issued ASUs not yet adopted and believes the adoption of these standards will not have a material impact on its consolidated financial statements.

Note 9 - Intellectual Property

12 Months Ended

Dec. 31, 2022

Intangible Assets Disclosure [Text Block]

9.	Intellectual Property

The components of gross intellectual property, accumulated amortization, and net intellectual property are as follows:

	December 31, 2022
	(in thousands)
	Gross Carrying Amount		Accumulated Amortization			Foreign Currency Translation Impact			Net Carrying Amount
Developed technology	$	68,838	$	(66,562	)	$	(874	)	$	1,402
Technology and patents purchased		400		(239	)		13			174
Total intellectual property	$	69,238	$	(66,801	)	$	(861	)	$	1,576

	December 31, 2021
	(in thousands)
	Gross Carrying Amount		Accumulated Amortization			Foreign Currency Translation Impact			Net Carrying Amount
Developed technology	$	68,838	$	(58,912	)	$	(262	)	$	9,664
Technology and patents purchased		400		(199	)		27			228
Total intellectual property	$	69,238	$	(59,111	)	$	(235	)	$	9,892

The weighted average remaining useful life of the developed technology and technology and patents purchased was 4.2 years and 4.3 years, respectively, as of December 31, 2022. The weighted average remaining useful life of the developed technology and technology and patents purchased was 1.6 years and 5.3 years, respectively as of December 31, 2021.

The estimated future amortization expense of intellectual property as of December 31, 2022 is as follows (in thousands):

	Year Ending December 31, 2022
2023	$	377
2024		377
2025		377
2026		377
2027		68
Total	$	1,576

Note 5 - Investments, Available-for-sale

12 Months Ended

Dec. 31, 2022

Investments in Debt and Marketable Equity Securities (and Certain Trading Assets) Disclosure [Text Block]

5.	Investments, available-for-sale

The aggregate fair values of investment securities along with cumulative unrealized gains and losses determined on an individual investment security basis and included in other comprehensive loss are as follows:

	December 31, 2022
	(in thousands)

	Amortized Cost		Unrealized Gain		Unrealized Loss			Fair Value		Short-term investments		Long-term investments
Commercial Paper	$	12,364	$	-	$	(49	)	$	12,315	$	12,315	$	-
Corporate Bonds		55,201		-		(447	)		54,754		50,889		3,865
U.S. Government Agencies		999		-		(8	)		991		991		-
Total Investments	$	68,564	$	-	$	(504	)	$	68,060	$	64,195	$	3,865

	December 31, 2021
	(in thousands)

	Amortized Cost		Unrealized Gain		Unrealized Loss			Fair Value		Short-term investments		Long-term investments
Commercial Paper	$	50,705	$	-	$	(46	)	$	50,659	$	50,660	$	-
Corporate Bonds		67,239		1		(202	)		67,038		29,602		37,435
Total Investments	$	117,944	$	1	$	(248	)	$	117,697	$	80,262	$	37,435

The following table summarizes the contractual maturities of the Company’s available-for-sale investments:

	December 31, 2022
	(in thousands)
	Amortized Cost		Fair Value
Mature in less than one year	$	64,662	$	64,195
Mature in one to two years		3,902		3,865
Total	$	68,564	$	68,060

Actual maturities may differ from contractual maturities because certain borrowers have the right to call or prepay certain obligations. There were no sales of investments for the years ended December 31, 2022 or 2021, respectively. There were no realized gains or losses for the years ended December 31, 2022. The company recorded an immaterial amount of gross realized losses for the year ended December 31, 2021 related to the maturity of investments.

Note 10 - Leases - Minimum Lease Payments (Details) $ in Thousands	Dec. 31, 2022 USD ($)
2023	$ 1,222
2024	1,136
2025	1,058
2026	837
2027	775
Thereafter	2,195
Total minimum lease payments	7,223
Less: Amount of lease payments representing interest	(1,685)
Present value of future minimum lease payments	$ 5,538

Note 7 - Inventories

12 Months Ended

Dec. 31, 2022

Inventory Disclosure [Text Block]

7.	Inventories

The components of inventories are as follows:

	December 31, 2022
	(in thousands)
	Gross Carrying Amount		Reserve Balance			Net Carrying Amount
Finished goods	$	15,337	$	(4,129	)	$	11,208
Raw materials		4,718		(2,173	)		2,545
Total inventories	$	20,055	$	(6,302	)	$	13,753

Current Portion	$	9,399	$	(1,115	)	$	8,284
Long-term portion		10,656		(5,187	)		5,469
Total inventories	$	20,055	$	(6,302	)	$	13,753

	December 31, 2021
	(in thousands)
	Gross Carrying Amount		Reserve Balance			Net Carrying Amount
Finished goods	$	13,066	$	(2,987	)	$	10,079
Raw materials		8,324		(2,695	)		5,629
Total inventories	$	21,390	$	(5,682	)	$	15,708

Current Portion	$	9,931	$	(1,297	)	$	8,634
Long-term portion		11,459		(4,385	)		7,074
Total inventories	$	21,390	$	(5,682	)	$	15,708

Note 8 - Property and Equipment (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Depreciation, Total	$ 3,368	$ 2,857

Note 2 - Summary of Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2022

Schedule of Property Plant and Equipment Useful Life [Table Text Block]

Note 3 - Revenue Recognition - Contract Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Contract Assets	$ 116	$ 91
Deferred Revenue	$ 465	$ 543

Note 15 - Basic and Diluted Net Loss Per Share

12 Months Ended

Dec. 31, 2022

Earnings Per Share [Text Block]

15.

Basic and Diluted Net Loss per Share

Basic net loss per common share is computed by dividing net loss attributable to common stockholders by the weighted average number of common shares outstanding during the period. Diluted net loss per common share is computed giving effect to all potential dilutive common shares that were outstanding during the period when the effect is dilutive. Potential dilutive common shares consist of incremental shares issuable upon exercise of stock options, restricted stock units, and warrants. No adjustments have been made to the weighted average outstanding common shares figures for the years ended December 31, 2022 or 2021 as the assumed exercise of outstanding options, warrants and restricted stock units would be anti-dilutive.

Potential common shares not included in calculating diluted net loss per share are as follows:

	December 31,
	2022		2021
Stock options		7,584,967		4,640,660
Stock warrants		1,021,076		1,120,300
Nonvested restricted stock units		8,483,491		3,839,030
Total		17,089,534		9,599,990

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Operating Activities:
Net loss	$ (75,561)	$ (62,462)
Adjustments to reconcile net loss to net cash and cash equivalents used in operating activities:
Depreciation	3,368	2,857
Amortization of intangible assets	7,708	11,254
Amortization of discounts and premiums on investments, net	565	409
Stock-based compensation	8,416	9,429
Gain on extinguishment of debt	0	(2,847)
Deferred tax expense	318	225
Change in inventory reserves	620	(492)
Bad debt expense	9	144
Property and equipment impairment	1,431	0
Loss on disposal of property and equipment	122	0
Change in fair value of warrant liabilities	(0)	1,981
Change in fair value of contingent consideration	(1,115)	(1,565)
Changes in operating assets and liabilities:
Accounts receivable	(1,528)	174
Inventories	(2,302)	(611)
Operating lease right-of-use assets	232	(4,254)
Prepaid expenses	(450)	146
Employee retention tax credit receivable	757	(1,311)
Other current and long-term assets	(2,101)	902
Accounts payable	35	1,614
Accrued employee compensation and benefits	4,523	(859)
Accrued expenses	(3,955)	384
Deferred revenue	(55)	(229)
Operating lease liabilities	26	4,452
Net cash and cash equivalents used in operating activities	(58,937)	(40,659)
Investing Activities:
Purchase of available-for-sale investments	(33,886)	(122,330)
Proceeds from maturities of available-for-sale investments	82,702	4,030
Purchase of property and equipment	(1,279)	(1,368)
Net cash and cash equivalents provided by (used in) investing activities	47,537	(119,668)
Financing Activities:
Proceeds from issuance of common stock, net of issuance costs	0	131,929
Taxes paid related to net share settlement of vesting of restricted stock units	(350)	(1,063)
Proceeds from exercise of stock options and warrants	18	30,839
Net cash and cash equivalents (used in) provided by financing activities	(332)	161,705
Effect of exchange rate changes on cash and cash equivalents	(81)	376
Net (decrease) increase in cash, cash equivalents and restricted cash	(11,813)	1,754
Cash, cash equivalents and restricted cash, beginning of period	19,283	17,529
Cash, cash equivalents and restricted cash, end of period	7,470	19,283
Supplemental Disclosure for Cash Flow Information
Cash paid for leases	984	1,490
Cash paid for taxes	165	170
Supplemental Schedule of Non-cash Investing and Financing Activities:
Transfer of inventories to property and equipment	2,693	3,244
Reclass of warrant liability to common stock and additional paid-in-capital	0	2,236
Lease liabilities arising from obtaining right-of-use assets	$ 577	$ 5,119

Note 13 - Stock-based Compensation - RSU Activity (Details) - Restricted Stock Units (RSUs) [Member]	12 Months Ended
	Dec. 31, 2022 $ / shares shares
Beginning of period, Restricted stock units, Unvested (in shares) \| shares	3,839,030
Beginning of period, Restricted stock units, Unvested, weighted average grant date fair value (in dollars per share) \| $ / shares	$ 2.36
Restricted stock units, Granted (in shares) \| shares	6,996,822
Restricted stock units, Granted, weighted average grant date fair value (in dollars per share) \| $ / shares	$ 0.71
Restricted stock units, Vested (in shares) \| shares	(2,076,663)
Restricted stock units, Vested, weighted average grant date fair value (in dollars per share) \| $ / shares	$ 2.34
Restricted stock units, Forfeited (in shares) \| shares	(275,698)
Restricted stock units, Forfeited, weighted average grant date fair value (in dollars per share) \| $ / shares	$ 1.19
Unvested (in shares) \| shares	8,483,491
Unvested December 31, 2022 (in dollars per share) \| $ / shares	$ 1.04

Note 13 - Stock-based Compensation - Stock Option Valuation Assumptions (Details)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Expected dividend yield	0.00%	0.00%
Minimum [Member]
Expected volatility	126.00%	118.00%
Risk-free interest rate	1.25%	0.33%
Expected life (in years) (Year)	3 years 9 months 18 days	3 years 9 months 18 days
Maximum [Member]
Expected volatility	133.00%	139.00%
Risk-free interest rate	4.40%	1.11%
Expected life (in years) (Year)	4 years 6 months	4 years 6 months

Note 17 - Segments and Geographic Areas

12 Months Ended

Dec. 31, 2022

Segment Reporting Disclosure [Text Block]

17.

Segments and Geographic Areas

The following table presents consolidated assets and long-lived assets by geographic area, which includes property and equipment, intellectual property, and operating lease assets:

	December 31, 2022
	Long-Lived Assets			Total Assets
U.S.		35	%		72	%

EMEA
Switzerland		46	%		24	%
Italy		8	%		2	%
Other		8	%		1	%
Total EMEA		62	%		27	%

Asia		3	%		1	%
Total		100	%		100	%

	December 31, 2021
	Long-Lived Assets			Total Assets
U.S.		26	%		77	%

EMEA
Switzerland		34	%		16	%
Italy		36	%		5	%
Other		4	%		1	%
Total EMEA		74	%		22	%

Asia		0	%		1	%
Total		100	%		100	%

The following table presents sales by geographic area based on the country in which the customer is based.

	Years Ended December 31,
	2022			2021


US		11	%		13	%
EMEA		77	%		62	%
Asia		12	%		25	%
Total		100	%		100	%

The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments.

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Note 3 - Revenue Recognition - Disaggregation of Revenue (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Revenue	$ 7,087	$ 8,232
UNITED STATES
Revenue	767	1,033
Non-US [Member]
Revenue	6,320	7,199
Systems [Member]
Revenue	2,551	3,286
Systems [Member] \| UNITED STATES
Revenue	0	0
Systems [Member] \| Non-US [Member]
Revenue	2,551	3,286
Instruments and Accessories [Member]
Revenue	1,776	2,113
Instruments and Accessories [Member] \| UNITED STATES
Revenue	211	273
Instruments and Accessories [Member] \| Non-US [Member]
Revenue	1,565	1,840
Service [Member]
Revenue	1,373	1,520
Service [Member] \| UNITED STATES
Revenue	300	383
Service [Member] \| Non-US [Member]
Revenue	1,073	1,137
Lease [Member]
Revenue	1,387	1,313
Lease [Member] \| UNITED STATES
Revenue	256	377
Lease [Member] \| Non-US [Member]
Revenue	$ 1,131	$ 936

Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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Note 12 - Income Taxes - Domestic and Foreign Components of Loss from Operations (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
United States	$ (44,802)	$ (32,094)
Foreign	(30,441)	(30,143)
Loss before income taxes	$ (75,243)	$ (62,237)

Amount of income (loss) from continuing operations, including income (loss) from equity method investments, before deduction of income tax expense (benefit), and income (loss) attributable to noncontrolling interest.

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Note 9 - Intellectual Property (Tables)

12 Months Ended

Dec. 31, 2022

Schedule of Finite-Lived Intangible Assets [Table Text Block]

	December 31, 2022
	(in thousands)
	Gross Carrying Amount		Accumulated Amortization			Foreign Currency Translation Impact			Net Carrying Amount
Developed technology	$	68,838	$	(66,562	)	$	(874	)	$	1,402
Technology and patents purchased		400		(239	)		13			174
Total intellectual property	$	69,238	$	(66,801	)	$	(861	)	$	1,576

	December 31, 2021
	(in thousands)
	Gross Carrying Amount		Accumulated Amortization			Foreign Currency Translation Impact			Net Carrying Amount
Developed technology	$	68,838	$	(58,912	)	$	(262	)	$	9,664
Technology and patents purchased		400		(199	)		27			228
Total intellectual property	$	69,238	$	(59,111	)	$	(235	)	$	9,892

Schedule of Finite-Lived Intangible Assets, Future Amortization Expense [Table Text Block]

	Year Ending December 31, 2022
2023	$	377
2024		377
2025		377
2026		377
2027		68
Total	$	1,576

Note 13 - Stock-based Compensation (Tables)

12 Months Ended

Dec. 31, 2022

Share-Based Payment Arrangement, Option, Activity [Table Text Block]

	Number of Shares			Weighted- Average Exercise Price		Weighted-Average Remaining Contractual Term (Years)
Balance at December 31, 2021		4,640,660		$	6.64		5.66
Granted		3,153,881			0.70
Forfeited		(129,134	)		1.60
Cancelled		(36,987	)		21.11
Exercised		(43,453	)		0.41
Balance at December 31, 2022		7,584,967		$	4.22		5.31

Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Vested and Expected to Vest, Exercisable [Table Text Block]

Number of

Shares

Weighted-

Average Exercise

Price

Weighted-Average

Remaining

Contractual Term

(Years)

Aggregate

Intrinsic Value

(Millions)

Exercisable at December 31, 2022

3,524,473

7.40

4.75

Vested or expected to vest at December 31, 2022

7,350,141

4.32

5.28

Schedule of Share-Based Payment Award, Stock Options, Valuation Assumptions [Table Text Block]

	Years Ended December 31,
	2022			2021
Expected dividend yield	0%			0%
Expected volatility	126%	-	133%	118%	-	139%
Risk-free interest rate	1.25%	-	4.40%	0.33%	-	1.11%
Expected life (in years)	3.8	-	4.5	3.8	-	4.5

Share-Based Payment Arrangement, Restricted Stock Unit, Activity [Table Text Block]

	Number of Restricted Stock Units Outstanding			Weighted- Average Grant Date Fair Value
Unvested December 31, 2021		3,839,030		$	2.36
Granted		6,996,822			0.71
Vested		(2,076,663	)		2.34
Forfeited		(275,698	)		1.19
Unvested December 31, 2022		8,483,491		$	1.04

Share-Based Payment Arrangement, Cost by Plan [Table Text Block]

	Years Ended December 31,
	2022		2021
	(in thousands)
Stock options	$	3,654	$	4,535
Restricted stock units		3,319		3,954
Performance restricted stock units		1,443		940
	$	8,416	$	9,429

Note 15 - Basic and Diluted Net Loss Per Share (Tables)

12 Months Ended

Dec. 31, 2022

Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share [Table Text Block]

	December 31,
	2022		2021
Stock options		7,584,967		4,640,660
Stock warrants		1,021,076		1,120,300
Nonvested restricted stock units		8,483,491		3,839,030
Total		17,089,534		9,599,990

Note 12 - Income Taxes

12 Months Ended

Dec. 31, 2022

Income Tax Disclosure [Text Block]

12.

Income Taxes

The components for the income tax expense are as follows for the years ended December 31 (in thousands):

	2022		2021
Current income taxes
Federal	$	-	$	-
State		-		-
Foreign		239		232
Deferred income taxes
Federal		-		-
State		-		-
Foreign		79		(7	)
Total income tax expense	$	318	$	225

The United States and foreign components of loss from operations before taxes are as follows for the years ended December 31 (in thousands):

	2022			2021

United States	$	(44,802	)	$	(32,094	)
Foreign		(30,441	)		(30,143	)
Total loss from operations before taxes	$	(75,243	)	$	(62,237	)

Significant components of the Company’s deferred tax assets consist of the following at December 31 (in thousands):

	2022			2021

Deferred Tax assets:
Stock-based compensation	$	2,840		$	2,440
Accrued expenses and other		2,538			2,423
Research credit carryforward		1,341			564
Fixed Assets		162			101
Capitalized start-up costs and other intangibles		921			1,109
Capitalized research costs		4,382			-
Net operating loss carryforwards		83,908			75,237
		96,092			81,874
Valuation Allowance		(94,704	)		(78,294	)
Net deferred tax asset		1,388			3,580
Deferred tax liabilities
Fixed assets and other		(1,214	)		(1,176	)
Purchase accounting intangibles		-			(2,116	)
Net deferred tax liability		(1,214	)		(3,292	)
Net deferred tax asset (liability)	$	174		$	288

During 2021, the Company completed an assessment of the available net operating loss and tax credit carryforwards under Section 382 and Section 383 of the Internal Revenue Code, respectively. The Company determined that it underwent multiple ownership changes throughout its history as defined under Section 382, including most recently in 2020. As a result of the identified ownership changes, the portion of net operating loss and tax credits carryforwards attributable to the pre-ownership change periods are subject to a substantial annual limitation under Sections 382 and 383 of the Internal Revenue Code. The Company has adjusted its net operating loss and tax credit carryforwards to address the impact of the 382 ownership changes. This resulted in a reduction of available Federal and State NOLs of $253 million and $204 million, respectively.

At December 31, 2022 and 2021, the Company has provided a full valuation allowance against its net deferred assets in the U.S., Canada, Italy, Luxembourg, Switzerland, and Taiwan tax jurisdictions, since realization of these benefits is not more likely than not. The valuation allowance increased approximately $16.4 million from the prior year. At December 31, 2022, the Company had U.S. federal net operating loss carryforwards of $419.4 million, of which $253 million are expected to expire unused under the limitations imposed by Internal Revenue Code Section 382 (as discussed above). Of the total amount of Federal NOLs (notwithstanding the 382 limitation), $254.5 million begin to expire in 2027, while the remaining $164.9 million carry forward indefinitely. At December 31, 2022, the Company had U.S. state net operating loss carryforwards of $328.9 million, of which $204 million are expected to expire unused under the state tax law equivalents of Internal Revenue Code Section 382. Of this amount (notwithstanding the 382 limitations), $317.4 million of state NOLs begin to expire in 2022, while the remaining $11.5 million carry forward indefinitely. At December 31, 2022, the Company had federal research credit carryforwards in the amount of $10.2 million. These carryforwards begin to expire in 2027. However, under the limitations of Internal Revenue Code Section 383, it is expected that $8.8 million of this carryforward will expire unused. The utilization of the federal net operating loss carryforwards and credit carryforwards will depend on the Company’s ability to generate sufficient taxable income prior to the expiration of the carryforwards.

At December 31, 2022, the Company had foreign operating loss carryforwards in Italy of approximately $24.6 million, which can be carried forward indefinitely; foreign operating loss carryforwards in Luxembourg of approximately $95.9 million, which will begin to expire in 2034; foreign operating loss carryforwards in Switzerland of approximately $116.5 million, which begin to expire in 2023, and foreign operating loss carryforwards in Canada of approximately $0.9 million, which begin to expire in 2040.

The Company has evaluated its tax positions to consider whether it has any unrecognized tax benefits. As of December 31, 2022, the Company had gross unrecognized tax benefits of approximately $0.3 million. Of the total, none would reduce the Company’s effective tax rate if recognized. The Company does not anticipate a significant change in total unrecognized tax benefits or the Company’s effective tax rate due to the settlement of audits or the expiration of statutes of limitations within the next twelve months. Furthermore, the Company does not expect any cash settlement with the taxing authorities as a result of these unrecognized tax benefits as the Company has sufficient unutilized carryforward attributes to offset the tax impact of these adjustments.

The following is a tabular reconciliation of the Company’s change in gross unrecognized tax positions at December 31 (in thousands):

	2022		2021

Beginning balance	$	141	$	-
Gross increases for tax positions related to current periods		194		141
Gross decreases related to 382 limitations		-		-
Ending balance	$	335	$	141

The Company recognizes interest and penalties related to uncertain tax positions in the provision for income taxes. As of December 31, 2022 and 2021, the Company had no accrued interest or penalties related to uncertain tax positions.

The Company has analyzed its filing positions in all significant federal, state, and foreign jurisdictions where it is required to file income tax returns, as well as open tax years in these jurisdictions. With few exceptions, the Company is no longer subject to United States Federal, state, and local tax examinations by tax authorities for years before 2019, although carryforward attributes that were generated prior to 2019 may still be adjusted upon examination by the taxing authorities if they either have been or will be used in a future period. No income tax returns are currently under examination by taxing authorities.

Taxes computed at the then-current statutory federal income tax rate of 21% are reconciled to the provision for income taxes as follows for the years ended December 31:

	2022						2021
	Amount			Percent of Pretax Earnings			Amount			Percent of Pretax Earnings
United States federal tax at statutory rate	$	(15,801	)		21.0	%	$	(13,070	)		21.0	%
State taxes (net of deferred benefit)		(2,912	)		3.9	%		(2,205	)		3.5	%
Nondeductible expenses		1,077			(1.4%	)		(440	)		0.7	%
Change in fair market value of contingent consideration		(283	)		0.4	%		(397	)		0.6	%
Warrant remeasurment and financing costs		-			-			502			(0.8%	)
Research & Development		(970	)		1.3	%		(705	)		1.1	%
Change in unrecognized tax benefits		194			(0.3%	)		141			(0.2%	)
Foreign tax rate differential		2,676			(3.6%	)		1,911			(3.1%	)
True-up to Stock Compensation - Cancellations		49			(0.1%	)		2,832			(4.6%	)
Change in enacted tax rates and other, net		(96	)		0.2	%		731			(1.0%	)
Change in valuation allowance		16,384			(21.8%	)		10,925			(17.6%	)
Income tax expense (benefit)	$	318			(0.4%	)	$	225			(0.4%	)

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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Reference 7: http://www.xbrl.org/2003/role/disclosureRef
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Reference 8: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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Note 4 - Cash, Cash Equivalents, and Restricted Cash

12 Months Ended

Dec. 31, 2022

Cash, Cash Equivalents, and Restricted Cash Disclosure [Text Block]

4.	Cash, Cash Equivalents, and Restricted Cash

Cash, cash equivalents and restricted cash consist of the following:

	December 31,		December 31,
	2022		2021
	(in thousands)
Cash	$	3,473	$	8,343
Money Market		2,856		5,287
Commerical Paper		-		4,499
Total cash and cash equivalents	$	6,329	$	18,129
Restricted Cash		1,141		1,154
Total	$	7,470	$	19,283

Restricted cash at December 31, 2022 and 2021 includes $1.1 million and $1.2 million, respectively, in cash accounts held as collateral primarily under the terms of an office operating lease, credit cards, automobile leases, and a performance guarantee required by the government of a country in which a Senhance System was sold in 2018.

Note 11 - Accrued Expenses

12 Months Ended

Dec. 31, 2022

Accrued Liabilities [Text Block]

11.

Accrued Expenses

The following table presents the components of accrued expenses:

	December 31, 2022		December 31, 2021
	(In thousands)
Consulting and other vendors	$	155	$	128
Other		—		124
Royalties		24		247
Legal and professional fees		275		503
Taxes and other assessments		839		615
Total	$	1,293	$	1,617

Note 9 - Intellectual Property - Intellectual Property (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Finite-Lived Intangible Assets, Gross	$ 69,238	$ 69,238
Finite-Lived Intangible Assets, Accumulated Amortization	(66,801)	(59,111)
Finite-Lived Intangible Assets, Foreign Currency Translation Impact	(861)	(235)
Intellectual property, net	1,576	9,892
Developed Technology Rights [Member]
Finite-Lived Intangible Assets, Gross	68,838	68,838
Finite-Lived Intangible Assets, Accumulated Amortization	(66,562)	(58,912)
Finite-Lived Intangible Assets, Foreign Currency Translation Impact	(874)	(262)
Intellectual property, net	1,402	9,664
Technology-Based Intangible Assets [Member]
Finite-Lived Intangible Assets, Gross	400	400
Finite-Lived Intangible Assets, Accumulated Amortization	(239)	(199)
Finite-Lived Intangible Assets, Foreign Currency Translation Impact	13	27
Intellectual property, net	$ 174	$ 228

Note 10 - Leases (Tables)

12 Months Ended

Dec. 31, 2022

Lease, Cost [Table Text Block]

	Years Ended December 31,
	2022		2021
	(in thousands)
Long-term Operating	$	1,557	$	1,826
Short-term Operating		-		-
Total Operating lease expense	$	1,557	$	1,826

Lessee, Operating Lease, Disclosure [Table Text Block]

	December 31, 2022			December 31, 2021
Weighted-average remaining lease term (in years)	6.8			7.8
Weighted-average discount rate	8.4%			7.8%
Incremental borrowing rate	6.1%	-	14.5%	6.1%	-	8.5%

Lessee, Operating Lease, Liability, Maturity [Table Text Block]

Fiscal Year
2023	$	1,222
2024		1,136
2025		1,058
2026		837
2027		775
Thereafter		2,195
Total minimum lease payments	$	7,223
Less: Amount of lease payments representing interest		(1,685	)
Present value of future minimum lease payments	$	5,538

Note 16 - Commitments and Contingencies - Purchase Orders Commitments (Details) - License and Supply Agreement [Member] - Senhance Surgical Robotic System Acquisition[Member] $ in Thousands	Dec. 31, 2022 USD ($)
2023	$ 5,976
2024	407
2025	313
2026	303
Total commitments	$ 6,999

Note 18 - Related Party Transactions (Details Textual) - USD ($)	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Asensus Surgical Europe S.à.R.L [Member] \| 1 Med S.A. [Member] \| Service Supply Agreement [Member]
Related Party Transaction, Expenses from Transactions with Related Party	$ 290,000	$ 186,000

Note 17 - Segments and Geographic Areas - Sales by Geographic Area (Details) - Revenue Benchmark [Member] - Geographic Concentration Risk [Member]	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
UNITED STATES
Concentration risk, percent	11.00%	13.00%
EMEA [Member]
Concentration risk, percent	77.00%	62.00%
Asia [Member]
Concentration risk, percent	12.00%	25.00%
All Countries [Member]
Concentration risk, percent	100.00%	100.00%

Note 12 - Income Taxes (Tables)

12 Months Ended

Dec. 31, 2022

Schedule of Components of Income Tax Expense (Benefit) [Table Text Block]

	2022		2021
Current income taxes
Federal	$	-	$	-
State		-		-
Foreign		239		232
Deferred income taxes
Federal		-		-
State		-		-
Foreign		79		(7	)
Total income tax expense	$	318	$	225

Schedule of Income before Income Tax, Domestic and Foreign [Table Text Block]

	2022			2021

United States	$	(44,802	)	$	(32,094	)
Foreign		(30,441	)		(30,143	)
Total loss from operations before taxes	$	(75,243	)	$	(62,237	)

Schedule of Deferred Tax Assets and Liabilities [Table Text Block]

	2022			2021

Deferred Tax assets:
Stock-based compensation	$	2,840		$	2,440
Accrued expenses and other		2,538			2,423
Research credit carryforward		1,341			564
Fixed Assets		162			101
Capitalized start-up costs and other intangibles		921			1,109
Capitalized research costs		4,382			-
Net operating loss carryforwards		83,908			75,237
		96,092			81,874
Valuation Allowance		(94,704	)		(78,294	)
Net deferred tax asset		1,388			3,580
Deferred tax liabilities
Fixed assets and other		(1,214	)		(1,176	)
Purchase accounting intangibles		-			(2,116	)
Net deferred tax liability		(1,214	)		(3,292	)
Net deferred tax asset (liability)	$	174		$	288

Schedule of Unrecognized Tax Benefits Roll Forward [Table Text Block]

	2022		2021

Beginning balance	$	141	$	-
Gross increases for tax positions related to current periods		194		141
Gross decreases related to 382 limitations		-		-
Ending balance	$	335	$	141

Schedule of Effective Income Tax Rate Reconciliation [Table Text Block]

	2022						2021
	Amount			Percent of Pretax Earnings			Amount			Percent of Pretax Earnings
United States federal tax at statutory rate	$	(15,801	)		21.0	%	$	(13,070	)		21.0	%
State taxes (net of deferred benefit)		(2,912	)		3.9	%		(2,205	)		3.5	%
Nondeductible expenses		1,077			(1.4%	)		(440	)		0.7	%
Change in fair market value of contingent consideration		(283	)		0.4	%		(397	)		0.6	%
Warrant remeasurment and financing costs		-			-			502			(0.8%	)
Research & Development		(970	)		1.3	%		(705	)		1.1	%
Change in unrecognized tax benefits		194			(0.3%	)		141			(0.2%	)
Foreign tax rate differential		2,676			(3.6%	)		1,911			(3.1%	)
True-up to Stock Compensation - Cancellations		49			(0.1%	)		2,832			(4.6%	)
Change in enacted tax rates and other, net		(96	)		0.2	%		731			(1.0%	)
Change in valuation allowance		16,384			(21.8%	)		10,925			(17.6%	)
Income tax expense (benefit)	$	318			(0.4%	)	$	225			(0.4%	)

Note 13 - Stock-based Compensation (Details Textual) - USD ($) $ in Millions		12 Months Ended
	Jul. 22, 2021	Dec. 31, 2022
Share-Based Payment Arrangement, Option [Member]
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total		$ 2.1
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)		1 year 6 months
Restricted Stock Units (RSUs) [Member]
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount, Total		$ 4.2
Share-Based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Period for Recognition (Year)		1 year 4 months 24 days
Asensus Surgical, Inc. Amended and Restated Incentive Compensation Plan [Member]
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Additional Shares Authorized (in shares)	22,000,000
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized (in shares)		32,072,308
Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Available for Grant (in shares)		11,038,824
Share-Based Compensation Arrangement by Share-Based Payment Award, Expiration Period (Year)		10 years

Note 13 - Stock-based Compensation - Stock Option Activity (Details) - $ / shares	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Options, Outstanding, Number of Shares (in shares)	4,640,660
Options, Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 6.64
Options, Outstanding, Weighted Average Remaining Contractual Term (Year)	5 years 3 months 21 days	5 years 7 months 28 days
Options, Granted, Number of Shares (in shares)	3,153,881
Options, Grants in Period, Weighted Average Exercise Price (in dollars per share)	$ 0.70
Options, Forfeited, Number of Shares (in shares)	(129,134)
Options, Forfeitures in Period, Weighted Average Exercise Price (in dollars per share)	$ 1.60
Options, Cancelled, Number of Shares (in shares)	(36,987)
Options, Expirations in Period, Weighted Average Exercise Price (in dollars per share)	$ 21.11
Options, Exercised, Number of Shares (in shares)	(43,453)
Options, Exercises in Period, Weighted Average Exercise Price (in dollars per share)	$ 0.41
Options, Outstanding, Number of Shares (in shares)	7,584,967	4,640,660
Options, Outstanding, Weighted Average Exercise Price (in dollars per share)	$ 4.22	$ 6.64

Note 6 - Fair Value (Tables)

12 Months Ended

Dec. 31, 2022

Fair Value, Assets Measured on Recurring Basis [Table Text Block]

	December 31, 2022
	(in thousands)

Description	Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Total
Assets measured at fair value
Cash and cash equivalents⁽¹⁾	$	6,329	$	-	$	-	$	6,329
Restricted cash		1,141		-		-		1,141
Short-term investments		-		64,195		-		64,195
Long-term investments		-		3,865		-		3,865
Total assets measured at fair value	$	7,470	$	68,060	$	-	$	75,530
Liabilities measured at fair value
Contingent consideration	$	-	$	-	$	1,256	$	1,256
Total liabilities measured at fair value	$	-	$	-	$	1,256	$	1,256

	December 31, 2021
	(in thousands)

Description	Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Total
Assets measured at fair value
Cash and cash equivalents⁽¹⁾	$	18,129	$	-	$	-	$	18,129
Restricted cash		1,154		-		-		1,154
Short-term investments		-		80,262		-		80,262
Long-term investments		-		37,435		-		37,435
Total assets measured at fair value	$	19,283	$	117,697	$	-	$	136,980
Liabilities measured at fair value
Contingent consideration	$	-	$	-	$	2,371	$	2,371
Total liabilities measured at fair value	$	-	$	-	$	2,371	$	2,371

Fair Value Measurement Inputs and Valuation Techniques [Table Text Block]

	Valuation Methodology	Significant Unobservable Input	December 31, 2022	December 31, 2021

Contingent consideration	Probability weighted income approach	Milestone dates	2032	2031
		Discount rate	16.5%	9.5%
		Revenue volatility	45.0%	39.0%
		EUR-to-USD exchange rate	1.07	1.14

Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block]

	Fair Value Measurement at Reporting Date (Level 3)
	(in thousands)
	Contingent consideration
Balance at December 31, 2020	$	3,936
Change in fair value		(1,565	)
Balance at December 31, 2021	$	2,371
Change in fair value		(1,115	)
Balance at December 31, 2022	$	1,256

Current portion	$	-
Long-term portion		1,256
Balance at December 31, 2022	$	1,256

Note 14 - Equity Offerings (Details Textual) - USD ($)			12 Months Ended
Note 14 - Equity Offerings (Details Textual) - USD ($)	Jan. 29, 2021	Jan. 12, 2021	Dec. 31, 2022	Dec. 31, 2021	Mar. 18, 2022	May 19, 2021	Oct. 09, 2020
Proceeds from Issuance of Common Stock, Net			$ 0	$ 131,929,000
Proceeds from Warrant Exercises				$ 30,600,000
The 2020 ATM Offering [Member]
Stock Offering Agreement, Maximum Share Value							$ 40,000,000.0
Public Offering [Member]
Stock Issued During Period, Shares, New Issues (in shares)	26,545,832
Shares Issued, Price Per Share (in dollars per share)	$ 3.00
Proceeds from Issuance of Common Stock, Net	$ 73,400,000
Registered Direct Offering [Member]
Stock Issued During Period, Shares, New Issues (in shares)		25,000,000
Shares Issued, Price Per Share (in dollars per share)		$ 1.25
Proceeds from Issuance of Common Stock, Net		$ 28,600,000
The 2021 ATM Offering [Member]
Stock Offering Agreement, Maximum Share Value						$ 100,000,000
The 2022 ATM Offering [Member]
Stock Offering Agreement, Maximum Share Value					$ 100,000,000.0
Stock Issued During Period, Shares, New Issues (in shares)			0

Note 6 - Fair Value - Quantitative Information about Inputs and Valuation Methodologies Used for Fair Value Measurements Classification (Details) - Senhance Surgical Robotic System Acquisition[Member] - Fair Value, Inputs, Level 3 [Member]	Dec. 31, 2022	Dec. 31, 2021
Measurement Input, Discount Rate [Member]
Contingent consideration, measurement input	0.165	0.095
Measurement Input, Price Volatility [Member]
Contingent consideration, measurement input	0.450	0.390
Measurement Input, Currency Exchange Rate [Member]
Contingent consideration, measurement input	1.07	1.14

Note 6 - Fair Value

12 Months Ended

Dec. 31, 2022

Fair Value Disclosures [Text Block]

6.	Fair Value

The following are categories of assets and liabilities measured at fair value on a recurring basis using quoted prices in active markets for identical assets (Level 1); significant other observable inputs (Level 2); and significant unobservable inputs (Level 3):

	December 31, 2022
	(in thousands)

Description	Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Total
Assets measured at fair value
Cash and cash equivalents⁽¹⁾	$	6,329	$	-	$	-	$	6,329
Restricted cash		1,141		-		-		1,141
Short-term investments		-		64,195		-		64,195
Long-term investments		-		3,865		-		3,865
Total assets measured at fair value	$	7,470	$	68,060	$	-	$	75,530
Liabilities measured at fair value
Contingent consideration	$	-	$	-	$	1,256	$	1,256
Total liabilities measured at fair value	$	-	$	-	$	1,256	$	1,256

⁽¹⁾Includes investments that are readily convertible to cash with original maturities of 90 days or less.

	December 31, 2021
	(in thousands)

Description	Quoted Prices in Active Markets for Identical Assets (Level 1)		Significant Other Observable Inputs (Level 2)		Significant Unobservable Inputs (Level 3)		Total
Assets measured at fair value
Cash and cash equivalents⁽¹⁾	$	18,129	$	-	$	-	$	18,129
Restricted cash		1,154		-		-		1,154
Short-term investments		-		80,262		-		80,262
Long-term investments		-		37,435		-		37,435
Total assets measured at fair value	$	19,283	$	117,697	$	-	$	136,980
Liabilities measured at fair value
Contingent consideration	$	-	$	-	$	2,371	$	2,371
Total liabilities measured at fair value	$	-	$	-	$	2,371	$	2,371

⁽¹⁾Includes investments that are readily convertible to cash with original maturities of 90 days or less.

The carrying values of accounts receivable, prepaid expenses, employee retention tax credit receivables, other current assets, accounts payable, accrued employee compensation and benefits, accrued expenses, deferred revenue, and other current liabilities as of December 31, 2022, and December 31, 2021, approximate their fair values due to the short-term nature of these items.

The Company’s financial liabilities consisted of contingent consideration payable to Three Heads Investment S.r.l., related to the Company’s 2015 acquisition of the Senhance Surgical System from an assignor to Three Heads Investment S.r.l. (the “Senhance Acquisition”). Adjustments associated with the change in fair value of contingent consideration are included in the Company’s consolidated statements of operations and comprehensive loss.

The following table presents quantitative information about the inputs and valuation methodologies used for the Company’s fair value measurements for contingent consideration utilizing a Monte-Carlo simulation as of December 31, 2022 and December 31, 2021:

	Valuation Methodology	Significant Unobservable Input	December 31, 2022	December 31, 2021

Contingent consideration	Probability weighted income approach	Milestone dates	2032	2031
		Discount rate	16.5%	9.5%
		Revenue volatility	45.0%	39.0%
		EUR-to-USD exchange rate	1.07	1.14

The following table presents the current and long-term portion of the contingent consideration for the year ended December 31, 2022 and summarizes the change in fair value, as determined by Level 3 inputs for the contingent consideration for the year ended December 31, 2022 and 2021:

	Fair Value Measurement at Reporting Date (Level 3)
	(in thousands)
	Contingent consideration
Balance at December 31, 2020	$	3,936
Change in fair value		(1,565	)
Balance at December 31, 2021	$	2,371
Change in fair value		(1,115	)
Balance at December 31, 2022	$	1,256

Current portion	$	-
Long-term portion		1,256
Balance at December 31, 2022	$	1,256

The entire disclosure for the fair value of financial instruments (as defined), including financial assets and financial liabilities (collectively, as defined), and the measurements of those instruments as well as disclosures related to the fair value of non-financial assets and liabilities. Such disclosures about the financial instruments, assets, and liabilities would include: (1) the fair value of the required items together with their carrying amounts (as appropriate); (2) for items for which it is not practicable to estimate fair value, disclosure would include: (a) information pertinent to estimating fair value (including, carrying amount, effective interest rate, and maturity, and (b) the reasons why it is not practicable to estimate fair value; (3) significant concentrations of credit risk including: (a) information about the activity, region, or economic characteristics identifying a concentration, (b) the maximum amount of loss the entity is exposed to based on the gross fair value of the related item, (c) policy for requiring collateral or other security and information as to accessing such collateral or security, and (d) the nature and brief description of such collateral or security; (4) quantitative information about market risks and how such risks are managed; (5) for items measured on both a recurring and nonrecurring basis information regarding the inputs used to develop the fair value measurement; and (6) for items presented in the financial statement for which fair value measurement is elected: (a) information necessary to understand the reasons for the election, (b) discussion of the effect of fair value changes on earnings, (c) a description of [similar groups] items for which the election is made and the relation thereof to the balance sheet, the aggregate carrying value of items included in the balance sheet that are not eligible for the election; (7) all other required (as defined) and desired information.

+ References + Details

Note 1 - Description of the Business

12 Months Ended

Dec. 31, 2022

Organization, Consolidation, Basis of Presentation, Business Description and Accounting Policies [Text Block]

1.	Description of the Business

Asensus Surgical, Inc. (formerly known as TransEnterix, Inc.) (the "Company") is a medical device company that is digitizing the interface between the surgeon and the patient to pioneer a new era of Performance-Guided Surgery™ by unlocking clinical intelligence for surgeons to enable consistently superior outcomes and a new standard of surgery. The Company is focused on the market development for and commercialization of the Senhance® Surgical System, which digitizes laparoscopic minimally invasive surgery, or MIS. The Senhance System is the first and only digital, multi-port laparoscopic platform designed to maintain laparoscopic MIS standards while providing digital benefits such as haptic feedback, robotic precision, comfortable ergonomics, advanced instrumentation including 3mm microlaparoscopic instruments, 5mm articulating instruments, eye-sensing camera control and fully-reusable standard instruments to help maintain per-procedure costs similar to traditional laparoscopy.

Note 14 - Equity Offerings (Tables)

12 Months Ended

Dec. 31, 2022

Schedule of Sales Under Sales Agency Agreement [Table Text Block]

	Year Ended December 31, 2021

Total shares of common stock sold		20,237,045
Average price per share	$	1.53
Gross proceeds	$	30,943
Commisssion earned by Sales Agents	$	928
Net proceeds	$	30,015

Consolidated Balance Sheets (Parentheticals) - $ / shares	Dec. 31, 2022	Dec. 31, 2021
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	750,000,000	750,000,000
Common stock, shares issued (in shares)	236,895,440	235,218,552
Common stock, shares outstanding (in shares)	236,895,440	235,218,552
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized (in shares)	25,000,000	25,000,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shares outstanding (in shares)	0	0

Note 16 - Commitments and Contingencies

12 Months Ended

Dec. 31, 2022

Commitments and Contingencies Disclosure [Text Block]

16.

Commitments and Contingencies

License and Supply Agreements

As part of the Company’s acquisition of the Senhance System in 2015, the Company assumed certain license and supply agreements. The Company has purchase orders with various suppliers for certain tooling, supplies, contract engineering and research services. Commitments related to license agreements and purchase orders are as follows (in thousands):

Fiscal Year
2023	$	5,976
2024		407
2025		313
2026		303
Total commitments	$	6,999

Note 2 - Summary of Significant Accounting Policies (Details Textual) $ in Thousands, € in Millions		12 Months Ended
	Jun. 10, 2021 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2022 EUR (€)	Dec. 31, 2021 USD ($)
Retained Earnings (Accumulated Deficit), Total		$ (860,935)		$ (785,374)
Working Capital		76,500
Overstated Raw Materials, Amount				2,500
Restricted Cash, Total		1,100		1,100
Debt Securities, Available-for-Sale, Realized Gain (Loss), Total		0		0
Accounts Receivable, Allowance for Credit Loss, Ending Balance		1,600		1,700
Accounts Receivable, Credit Loss Expense (Reversal)		9		144
Property, Plant and Equipment, Including Purchased Software, Impairment Charges		1,400		0
Other Income, Employer Retention Tax Credit		0		1,311
Proceeds From Employee Retention Tax Credit		700
Employer Retention Tax Credit Receivable		554		1,311
Letters of Credit Outstanding, Amount		0
Business Combination, Contingent Consideration, Liability, Total		$ 1,256		$ 2,371
Period Of Service Sale Arrangement (Year)		5 years	5 years
Period of Service Sale Arrangement at Stated Service Price (Year)		4 years	4 years
Lessor, Operating Lease, Payments to be Received, Total		$ 2,200
Number of Operating Segments		1	1
Senhance Surgical Robotic System Acquisition[Member]
Business Combination, Contingent Consideration, Liability, Total		$ 1,300
Business Combination, Contingent Consideration, Liability, Related Milestone \| €			€ 15
Letter of Credit [Member]
Line of Credit Facility, Remaining Borrowing Capacity		$ 600
Paycheck Protection Program CARES Act [Member]
Debt Instrument, Decrease, Forgiveness	$ 2,800
Minimum [Member]
Lessee, Operating Lease, Term of Contract (Year)		1 year
Lessee, Operating Lease, Renewal Term (Year)		1 year
Minimum [Member] \| Senhance Surgical Robotic System Acquisition[Member]
Business Combination Contingent Consideration Arrangements Target Revenue \| €			€ 25
Maximum [Member]
Lessee, Operating Lease, Term of Contract (Year)		10 years
Lessee, Operating Lease, Renewal Term (Year)		6 years
Patents [Member]
Finite-Lived Intangible Asset, Useful Life (Year)		10 years	10 years
Developed Technology Rights [Member] \| Minimum [Member]
Finite-Lived Intangible Asset, Useful Life (Year)		5 years	5 years
Developed Technology Rights [Member] \| Maximum [Member]
Finite-Lived Intangible Asset, Useful Life (Year)		7 years	7 years
Intellectual Property [Member]
Impairment of Intangible Assets, Finite-lived		$ 0
Accounts Receivable [Member] \| Customer Concentration Risk [Member] \| One Customer [Member]
Number of Major Customers		1	1
Concentration Risk, Percentage		69.00%	69.00%
Accounts Receivable [Member] \| Customer Concentration Risk [Member] \| Three Customers [Member]
Number of Major Customers				3
Accounts Receivable [Member] \| Customer Concentration Risk [Member] \| Customer One [Member]
Concentration Risk, Percentage				26.00%
Accounts Receivable [Member] \| Customer Concentration Risk [Member] \| Customer Two [Member]
Concentration Risk, Percentage				20.00%
Accounts Receivable [Member] \| Customer Concentration Risk [Member] \| Customer Three [Member]
Concentration Risk, Percentage				14.00%
Revenue Benchmark [Member] \| Customer Concentration Risk [Member] \| One Customer [Member]
Number of Major Customers		1	1
Concentration Risk, Percentage		47.00%	47.00%
Revenue Benchmark [Member] \| Customer Concentration Risk [Member] \| Customer One [Member]
Concentration Risk, Percentage				36.00%
Revenue Benchmark [Member] \| Customer Concentration Risk [Member] \| Customer Two [Member]
Concentration Risk, Percentage				16.00%
Revenue Benchmark [Member] \| Customer Concentration Risk [Member] \| Two Customers [Member]
Number of Major Customers				2

Note 3 - Revenue Recognition

12 Months Ended

Dec. 31, 2022

Revenue from Contract with Customer [Text Block]

3.	Revenue Recognition

The following table presents revenue disaggregated by type and geography:

	Years Ended December 31,
	2022		2021
	(in thousands)
U.S.
Systems	$	-	$	-
Instruments and accessories		211		273
Services		300		383
Leases		256		377
Total U.S. revenue		767		1,033

Outside of U.S. ("OUS")
Systems		2,551		3,286
Instruments and accessories		1,565		1,840
Services		1,073		1,137
Leases		1,131		936
Total OUS revenue		6,320		7,199

Total
Systems		2,551		3,286
Instruments and accessories		1,776		2,113
Services		1,373		1,520
Leases		1,387		1,313
Total revenue	$	7,087	$	8,232

Remaining Performance Obligations

The transaction price allocated to remaining performance obligations relates to amounts allocated to products and services for which the revenue has not yet been recognized. A significant portion of this amount relates to service obligations performed under the Company's system sales contracts that will be invoiced and recognized as revenue in future periods. Transaction price allocated to remaining performance obligations as of December 31, 2022 was $1.1 million, which is expected to be recognized over one to four years.

Contract Assets and Liabilities

Deferred revenue for the periods presented was primarily related to service obligations, for which the service fees are billed up-front, generally annually. The associated deferred revenue is generally recognized ratably over the service period. The Company did not have any significant impairment losses on its contract assets for the periods presented. Revenue recognized for the years ended December 31, 2022 and 2021 that was included in the deferred revenue balance at the beginning of each reporting period was $0.5 million and $0.6 million, respectively.

The following information summarizes the Company’s contract assets and liabilities:

	December 31, 2022		December 31, 2021
	(in thousands)
Contract Assets	$	116	$	91
Deferred Revenue	$	465	$	543

The entire disclosure of revenue from contract with customer to transfer good or service and to transfer nonfinancial asset. Includes, but is not limited to, disaggregation of revenue, credit loss recognized from contract with customer, judgment and change in judgment related to contract with customer, and asset recognized from cost incurred to obtain or fulfill contract with customer. Excludes insurance and lease contracts.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
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Reference 10: http://www.xbrl.org/2003/role/disclosureRef
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Note 5 - Investments, Available-for-sale - Summary of Investment Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Amortized Cost	$ 68,564	$ 117,944
Unrealized Gain	0	1
Unrealized Loss	(504)	(248)
Fair Value	68,060	117,697
Short-term investments	64,195	80,262
Long-term investments	3,865	37,435
Commercial Paper [Member]
Amortized Cost	12,364	50,705
Unrealized Gain	0	0
Unrealized Loss	(49)	(46)
Fair Value	12,315	50,659
Short-term investments	12,315	50,660
Long-term investments	0	0
Corporate Debt Securities [Member]
Amortized Cost	55,201	67,239
Unrealized Gain	0	1
Unrealized Loss	(447)	(202)
Fair Value	54,754	67,038
Short-term investments	50,889	29,602
Long-term investments	3,865	$ 37,435
US Government Agencies Debt Securities [Member]
Amortized Cost	999
Unrealized Gain	0
Unrealized Loss	(8)
Fair Value	991
Short-term investments	991
Long-term investments	$ 0

Document And Entity Information - USD ($)	12 Months Ended
Document And Entity Information - USD ($)	Dec. 31, 2022	Feb. 24, 2023	Jun. 30, 2022
Document Information [Line Items]
Entity Central Index Key	0000876378
Entity Registrant Name	ASENSUS SURGICAL, INC.
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Document Fiscal Period Focus	FY
Document Fiscal Year Focus	2022
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2022
Document Transition Report	false
Entity File Number	0-19437
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	11-2962080
Entity Address, Address Line One	1 TW Alexander Drive, Suite 160
Entity Address, City or Town	Durham
Entity Address, State or Province	NC
Entity Address, Postal Zip Code	27703
City Area Code	919
Local Phone Number	765-8400
Title of 12(b) Security	Common Stock $0.001 par value per share
Trading Symbol	ASXC
Security Exchange Name	NYSE
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Non-accelerated Filer
Entity Small Business	true
Entity Emerging Growth Company	false
ICFR Auditor Attestation Flag	false
Entity Shell Company	false
Entity Public Float			$ 93,100,000
Entity Common Stock, Shares Outstanding		239,279,746
Auditor Name	BDO USA, LLP
Auditor Location	Raleigh, NC
Auditor Firm ID	243

Note 7 - Inventories - Components of Inventories (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Finished goods, gross	$ 15,337	$ 13,066
Finished goods, reserve	(4,129)	(2,987)
Finished goods, net	11,208	10,079
Raw materials, gross	4,718	8,324
Raw materials, reserve	(2,173)	(2,695)
Raw materials, net	2,545	5,629
Total inventories, gross	20,055	21,390
Total inventories, reserve	(6,302)	(5,682)
Total inventories, net	13,753	15,708
Current Portion, gross	9,399	9,931
Current Portion, reserve	(1,115)	(1,297)
Inventories	8,284	8,634
Long-term portion, gross	10,656	11,459
Long-term portion, reserve	(5,187)	(4,385)
Inventories, net of current portion	$ 5,469	$ 7,074

Consolidated Statements of Changes in Stockholders' Equity - USD ($) $ in Thousands	Common Stock [Member]	Treasury Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	AOCI Attributable to Parent [Member]	Total
Balance (in shares) at Dec. 31, 2020	116,231,000	0
Balance at Dec. 31, 2020	$ 116	$ 0	$ 781,397	$ (722,912)	$ 2,968	$ 61,569
Stock-based compensation	$ 0		9,429	0	0	9,429
Issuance of common stock, net of issuance costs (in shares)	71,787,000	0
Issuance of common stock, net of issuance costs	$ 72	$ 0	131,857	0	0	131,929
Exercise of stock options and warrants (in shares)	45,630,000	0
Exercise of stock options and warrants	$ 46	$ 0	33,029	0	0	33,075
Award of restricted stock units (in shares)	1,571,000
Award of restricted stock units	$ 1
Return of common stock to pay withholding taxes on restricted stock (in shares)	0	320,000
Return of common stock to pay withholding taxes on restricted stock	$ 0	$ 0	(1,063)	0	0	(1,063)
Cancellation of treasury stock (in shares)	0	(320,000)
Cancellation of treasury stock	$ 0	$ 0	0	0	0	0
Other comprehensive loss	0	0	0	0	(3,232)	(3,232)
Net loss	$ 0	$ 0		(62,462)	0	(62,462)
Balance (in shares) at Dec. 31, 2021	235,219,000	0
Balance at Dec. 31, 2021	$ 235	$ 0	954,649	(785,374)	(264)	169,246
Stock-based compensation	$ 0		8,416	0	0	8,416
Award of restricted stock units (in shares)	1,633,000	0
Award of restricted stock units	$ 2	$ 0	0	0	0	2
Return of common stock to pay withholding taxes on restricted stock (in shares)	0	443,000
Return of common stock to pay withholding taxes on restricted stock	$ 0	$ 0	(352)	0	0	(352)
Cancellation of treasury stock (in shares)	0	(443,000)
Cancellation of treasury stock	$ 0	$ 0	0	0	0	0
Other comprehensive loss	0			0	(2,124)	(2,124)
Net loss	$ 0			(75,561)	0	$ (75,561)
Exercise of stock options (in shares)	43,000	0				43,453
Exercise of stock options	$ 0	$ 0	18	0	0	$ 18
Balance (in shares) at Dec. 31, 2022	236,895,000	0
Balance at Dec. 31, 2022	$ 237	$ 0	$ 962,731	$ (860,935)	$ (2,388)	$ 99,645

Note 3 - Revenue Recognition 2 (Details Textual) - Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2023-01-01 $ in Millions	Dec. 31, 2022 USD ($)
Revenue, Remaining Performance Obligation, Amount	$ 1.1
Minimum [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period (Year)	1 year
Maximum [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period (Year)	4 years

Note 18 - Related Party Transactions

12 Months Ended

Dec. 31, 2022

18.

Related Party Transactions

In March 2018, Asensus Surgical Europe S.à r.l. entered into a Service Supply Agreement with 1 Med S.A. for certain regulatory consulting services. Andrea Biffi, a current member of the Company’s Board of Directors, owns a non-controlling interest in 1 Med S.A. Expenses under the Service Supply Agreement were approximately $290,000 and $186,000 for the years ended December 31, 2022 and 2021, respectively.

Note 6 - Fair Value - Summary of Change in Fair Value for Warrants and Contingent Consideration (Details) - Warrant [Member] - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Balance	$ 2,371	$ 3,936
Change in fair value	(1,115)	(1,565)
Balance	1,256	$ 2,371
Current portion	0
Long-term portion	$ 1,256

Note 12 - Income Taxes - Deferred Tax Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Stock-based compensation	$ 2,840	$ 2,440
Accrued expenses and other	2,538	2,423
Research credit carryforward	1,341	564
Fixed Assets	162	101
Net operating loss carryforwards	83,908	75,237
Deferred Tax Assets, Gross, Total	96,092	81,874
Valuation Allowance	(94,704)	(78,294)
Net deferred tax asset	1,388	3,580
Fixed assets and other	(1,214)	(1,176)
Purchase accounting intangibles	0	(2,116)
Net deferred tax liability	(1,214)	(3,292)
Net deferred tax asset (liability)	174	288
Start-up Costs and Other Intangibles [Member]
Capitalized costs	921	1,109
Research Tax Credit Carryforward [Member]
Capitalized costs	$ 4,382	$ 0

Note 9 - Intellectual Property (Details Textual) - Weighted Average [Member]	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Developed Technology Rights [Member]
Finite-Lived Intangible Assets, Remaining Amortization Period (Year)	4 years 2 months 12 days	1 year 7 months 6 days
Technology-Based Intangible Assets [Member]
Finite-Lived Intangible Assets, Remaining Amortization Period (Year)	4 years 3 months 18 days	5 years 3 months 18 days

Note 15 - Basic and Diluted Net Loss Per Share - Antidilutive Securities Excluded from Computation of Earnings Per Share (Details) - shares	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Antidilutive Securities Excluded from Computation of Earnings Per Share (in shares)	17,089,534	9,599,990
Share-Based Payment Arrangement, Option [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share (in shares)	7,584,967	4,640,660
Warrant [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share (in shares)	1,021,076	1,120,300
Restricted Stock Units (RSUs) [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share (in shares)	8,483,491	3,839,030

Note 10 - Leases - Components of Operating Lease Expense (Details) - General and Administrative Expense [Member] - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Long-term Operating	$ 1,557	$ 1,826
Short-term Operating	0	0
Total Operating lease expense	$ 1,557	$ 1,826

Note 8 - Property and Equipment - Summary of Property and Equipment (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Property, plant and equipment, gross	$ 22,222	$ 20,660
Accumulated depreciation and amortization	(12,680)	(9,689)
Property and equipment, net	9,542	10,971
Machinery, Manufacturing and Demonstration Equipment [Member]
Property, plant and equipment, gross	8,450	8,289
Operating Lease Assets [Member]
Property, plant and equipment, gross	10,251	10,143
Computer Equipment [Member]
Property, plant and equipment, gross	600	325
Furniture and Fixtures [Member]
Property, plant and equipment, gross	831	644
Leasehold Improvements [Member]
Property, plant and equipment, gross	1,654	1,259
Construction in Progress [Member]
Property, plant and equipment, gross	$ 436

Note 3 - Revenue Recognition 1 (Details Textual) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Contract with Customer, Liability, Revenue Recognized	$ 0.5	$ 0.6

Note 11 - Accrued Expenses (Tables)

12 Months Ended

Dec. 31, 2022

Schedule of Accrued Liabilities [Table Text Block]

	December 31, 2022		December 31, 2021
	(In thousands)
Consulting and other vendors	$	155	$	128
Other		—		124
Royalties		24		247
Legal and professional fees		275		503
Taxes and other assessments		839		615
Total	$	1,293	$	1,617

Note 8 - Property and Equipment

12 Months Ended

Dec. 31, 2022

Property, Plant and Equipment Disclosure [Text Block]

8.	Property and Equipment

Property and equipment consisted of the following:

	December 31, 2022			December 31, 2021
	(In thousands)
Machinery, manufacturing, and demonstration equipment	$	8,450		$	8,289
Operating lease assets - Senhance System leasing		10,251			10,143
Computer equipment		600			325
Furniture		831			644
Leasehold improvements		1,654			1,259
Construction in process		436		‑
Total property and equipment		22,222			20,660
Accumulated depreciation and amortization		(12,680	)		(9,689	)
Property and equipment, net	$	9,542		$	10,971

Depreciation expense was approximately $3.4 million and $2.9 million for the years ended December 31, 2022 and 2021, respectively.

Note 9 - Intellectual Property - Amortization Expense of Intangible Assets (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Total	$ 1,576	$ 9,892
Intellectual Property [Member]
2023	377
2024	377
2025	377
2026	377
2027	68
Total	$ 1,576	$ 9,892

Note 17 - Segments and Geographic Areas - Consolidated Assets and Long Lived Assets by Geographic Area (Details) - Geographic Concentration Risk [Member]	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Long-lived Assets [Member] \| UNITED STATES
Percentage	35.00%	26.00%
Long-lived Assets [Member] \| SWITZERLAND
Percentage	46.00%	34.00%
Long-lived Assets [Member] \| ITALY
Percentage	8.00%	36.00%
Long-lived Assets [Member] \| Other Countries in EMEA [Member]
Percentage	8.00%	4.00%
Long-lived Assets [Member] \| Europe, Middle East, and Africa [Member]
Percentage	62.00%	74.00%
Long-lived Assets [Member] \| Asia [Member]
Percentage	3.00%	0.00%
Long-lived Assets [Member] \| All Countries [Member]
Percentage	100.00%	100.00%
Assets, Total [Member] \| UNITED STATES
Percentage	72.00%	77.00%
Assets, Total [Member] \| SWITZERLAND
Percentage	24.00%	16.00%
Assets, Total [Member] \| ITALY
Percentage	2.00%	5.00%
Assets, Total [Member] \| Other Countries in EMEA [Member]
Percentage	1.00%	1.00%
Assets, Total [Member] \| Europe, Middle East, and Africa [Member]
Percentage	27.00%	22.00%
Assets, Total [Member] \| Asia [Member]
Percentage	1.00%	1.00%
Assets, Total [Member] \| All Countries [Member]
Percentage	100.00%	100.00%

Note 12 - Income Taxes - Effective Income Tax Reconciliation (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
United States federal tax at statutory rate, amount	$ (15,801)	$ (13,070)
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	21.00%	21.00%
State taxes (net of deferred benefit), amount	$ (2,912)	$ (2,205)
State taxes (net of deferred benefit), percent	3.90%	3.50%
Nondeductible expenses, amount	$ 1,077	$ (440)
Nondeductible expenses, percent	(1.40%)	0.70%
Change in fair market value of contingent consideration, amount	$ (283)	$ (397)
Change in fair market value of contingent consideration, percent	0.40%	0.60%
Warrant remeasurment and financing costs, amount	$ 0	$ 502
Warrant remeasurment and financing costs, percent	0.00%	(0.80%)
Research & Development, amount	$ (970)	$ (705)
Research & Development, percent	1.30%	1.10%
Change in unrecognized tax benefits, amount	$ 194	$ 141
Change in unrecognized tax benefits, percent	(0.30%)	(0.20%)
Foreign tax rate differential, amount	$ 2,676	$ 1,911
Foreign tax rate differential, percent	(3.60%)	(3.10%)
True-up to Stock Compensation - Cancellations, amount	$ 49	$ 2,832
True-up to Stock Compensation - Cancellations, percent	(0.10%)	(4.60%)
Change in enacted tax rates and other, net, amount	$ (96)	$ 731
Change in enacted tax rates and other, net, percent	0.20%	(1.00%)
Change in valuation allowance, amount	$ 16,384	$ 10,925
Change in valuation allowance, percent	(21.80%)	(17.60%)
Total income tax expense	$ 318	$ 225
Income tax expense (benefit), percent	(0.40%)	(0.40%)

Note 5 - Investments, Available-for-sale (Tables)

12 Months Ended

Dec. 31, 2022

Debt Securities, Available-for-Sale [Table Text Block]

	December 31, 2022
	(in thousands)

	Amortized Cost		Unrealized Gain		Unrealized Loss			Fair Value		Short-term investments		Long-term investments
Commercial Paper	$	12,364	$	-	$	(49	)	$	12,315	$	12,315	$	-
Corporate Bonds		55,201		-		(447	)		54,754		50,889		3,865
U.S. Government Agencies		999		-		(8	)		991		991		-
Total Investments	$	68,564	$	-	$	(504	)	$	68,060	$	64,195	$	3,865

	December 31, 2021
	(in thousands)

	Amortized Cost		Unrealized Gain		Unrealized Loss			Fair Value		Short-term investments		Long-term investments
Commercial Paper	$	50,705	$	-	$	(46	)	$	50,659	$	50,660	$	-
Corporate Bonds		67,239		1		(202	)		67,038		29,602		37,435
Total Investments	$	117,944	$	1	$	(248	)	$	117,697	$	80,262	$	37,435

Investments Classified by Contractual Maturity Date [Table Text Block]

	December 31, 2022
	(in thousands)
	Amortized Cost		Fair Value
Mature in less than one year	$	64,662	$	64,195
Mature in one to two years		3,902		3,865
Total	$	68,564	$	68,060

Note 16 - Commitments and Contingencies (Tables)

12 Months Ended

Dec. 31, 2022

Contractual Obligation, Fiscal Year Maturity [Table Text Block]

Fiscal Year
2023	$	5,976
2024		407
2025		313
2026		303
Total commitments	$	6,999

Note 6 - Fair Value - Summary of Assets and Liabilities Measured at Fair Value on Recurring Basis (Details) - USD ($)
$ in Thousands

Dec. 31, 2022

Dec. 31, 2021

^[1]

$ 6,329

$ 18,129

1,141

1,154

64,195

80,262

3,865

37,435

75,530

136,980

1,256

2,371

Fair Value, Inputs, Level 1 [Member]

1,256

2,371

^[1]

6,329

18,129

1,141

1,154

7,470

19,283

Fair Value, Inputs, Level 2 [Member]

^[1]

64,195

80,262

3,865

37,435

68,060

117,697

Fair Value, Inputs, Level 3 [Member]

^[1]

1,256

2,371

$ 1,256

$ 2,371

[1]	Includes investments that are readily convertible to cash with original maturities of 90 days or less.

Note 2 - Summary of Significant Accounting Policies

12 Months Ended

Dec. 31, 2022

Significant Accounting Policies [Text Block]

2.	Summary of Significant Accounting Policies

Basis of Presentation

The accompanying consolidated financial statements have been prepared in accordance with U.S. generally accepted accounting principles (“U.S. GAAP”) and include the accounts of the Company and its direct and indirect wholly owned subsidiaries.

Going Concern

The Company's consolidated financial statements are prepared using U.S. GAAP applicable to a going concern, which contemplate the realization of assets and liquidation of liabilities in the normal course of business. The Company had an accumulated deficit of $860.9 million and working capital of $76.5 million as of December 31, 2022. The Company has not established sufficient sales revenues to cover its operating costs and requires additional capital to proceed with its operating plan. The ability of the Company to continue as a going concern is dependent on the Company obtaining adequate capital to fund operating losses until it becomes profitable.

The Company will need to obtain additional financing to proceed with its business plan. Management's plan to obtain additional resources for the Company may include additional sales of equity, traditional financing, such as loans, entry into a strategic collaboration, entry into an out-licensing arrangement or provision of additional distribution rights in some or all of our markets. However, management cannot provide any assurance that the Company will be successful in accomplishing any or all of its plans. The ability to successfully resolve these factors raise substantial doubt about the Company’s ability to meet its existing obligations, and to continue as a going concern within one year from the date that these financial statements are issued. The consolidated financial statements of the Company do not include any adjustments that may result from the outcome of these aforementioned uncertainties.

Principles of Consolidation and Foreign Currency Considerations

The accompanying consolidated financial statements include the accounts of the Company and its direct and indirect wholly owned subsidiaries, Asensus Surgical US, Inc., Asensus International, Inc., Asensus Surgical Italia S.r.l., Asensus Surgical Europe S.à r.l., Asensus Surgical Taiwan Ltd., Asensus Surgical Japan K.K., Asensus Surgical Israel Ltd., Asensus Surgical Netherlands B.V., and Asensus Surgical Canada, Inc. All inter-company accounts and transactions have been eliminated in consolidation.

The functional currency of the Company’s operational foreign subsidiaries is predominantly the Euro. The assets and liabilities of the Company’s foreign subsidiaries are translated into U.S. dollars at exchange rates in effect at the balance sheet date. Income and expense items are translated at the average exchange rates prevailing during the period. The cumulative translation effect for a subsidiary using a functional currency other than the U.S. dollar is included in accumulated other comprehensive loss as a separate component of stockholders’ equity.

The Company’s intercompany accounts are denominated in the functional currency of the foreign subsidiary. Gains and losses resulting from the remeasurement of intercompany receivables that the Company considers to be of a long-term investment nature are recorded as a cumulative translation adjustment in accumulated other comprehensive loss as a separate component of stockholders’ equity, while gains and losses resulting from the remeasurement of intercompany receivables from a foreign subsidiary for which the Company anticipates settlement in the foreseeable future are recorded in the consolidated statements of operations and comprehensive loss. The net gains and losses included in net loss in the consolidated statements of operations and comprehensive loss for the years ended December 31, 2022 and 2021 were not material.

Reclassifications

Certain amounts reported previously have been reclassified to conform to the current year presentation, with no effect on stockholders’ equity or net loss as previously reported. Revenue and cost of revenue for leases were historically included in product and service revenue and corresponding cost of revenue on the consolidated statements of operations and comprehensive loss for the year ended December 31, 2021. Accrued employee compensation and benefits were historically included in accrued expenses and other current liabilities on the consolidated balance sheets for the year ended December 31, 2021.

Revision of Previously Disclosed Amounts

During the course of preparing the Company’s unaudited consolidated financial statements as of and for the six months ended June 30, 2022, the Company determined that its December 31, 2021 inventory footnote presentation overstated raw materials and understated finished goods by $2.5 million. For comparative purposes, Note 7 – Inventories, has been revised to reflect the adjustment to raw materials and finished goods as of December 31, 2021. The revision had no effect on the previously reported total gross and net carrying value of inventory. The revision also had no effect on the previously reported consolidated balance sheets, statements of operations and comprehensive loss, cash flows and stockholders’ equity.

Risk and Uncertainties

The Company is subject to risks similar to other similarly sized companies in the medical device industry. These risks include, without limitation: negative impacts on the Company's operations caused by the COVID-19 pandemic and other geopolitical factors; the historical lack of profitability; the Company’s ability to raise additional capital; the success of its market development efforts; its ability to successfully develop, clinically test and commercialize its products; the timing and outcome of the regulatory review process for its products; changes in the healthcare regulatory environments of the United States, the European Union, Japan, Taiwan, and other countries in which the Company operates or intends to operate; its ability to attract and retain key management, marketing and scientific personnel; its ability to successfully prepare, file, prosecute, maintain, defend and enforce patent claims and other intellectual property rights; its ability to successfully transition from a research and development company to a marketing, sales and distribution company; competition in the market for robotic surgical devices; and its ability to identify and pursue development of additional products.

Use of Estimates

The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and the disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates. Significant items subject to such estimates and assumptions include impairment considerations for long-lived assets, fair value estimates related to contingent consideration, stock compensation expense, revenue recognition, short-term and long-term investments, excess and obsolete inventory reserves, inventory classification between current and non-current, measurement of lease liabilities and corresponding right-of-use (“ROU”) assets, and deferred tax asset valuation allowances.

Cash and Cash Equivalents, Restricted Cash, and Investments

The Company considers all highly liquid investments with original maturities of 90 days or less at the time of purchase to be cash equivalents.

Restricted cash as of December 31, 2022 and 2021 includes $1.1 million in cash accounts held as collateral primarily under the terms of an office operating lease, credit cards, and automobile leases.

The Company’s investments as of December 31, 2022 consisted of commercial paper, corporate bonds, and United States government agencies and were classified as available-for-sale. Investments classified as available-for-sale are measured at fair value, and net unrealized gains and losses are recorded as a component of accumulated other comprehensive loss on the consolidated balance sheets until realized. The amortized cost of debt securities is adjusted for amortization of premiums and accretion of discounts to maturity computed under the effective interest method. Such amortization and accretion is included in interest expense, net. There were no gross realized gains or loss for the year ended December 31, 2022. The Company recognized an immaterial amount of gross realized losses for the year ended December 31, 2021. There were no gross realized gains for the year ended December 31, 2021.

Investments with remaining maturities at date of purchase greater than 90 days and remaining maturities as of the reporting period less than one year are classified as short-term investments. Investments with remaining maturities greater than one year are classified as long-term investments.

There have been no credit losses for the years ended December 31, 2022 and 2021, and no allowance for credit losses as of December 31, 2022. Factors considered in determining whether a credit loss exists include credit ratings and other qualitative factors for each security type in the portfolio.

Fair Value Measurements

The Company measures the fair value of money market funds, certain U.S. treasury securities, and equity investments with readily determinable value based on quoted prices in active markets for identical assets as Level 1 securities. Marketable securities measured at fair value using Level 2 inputs are primarily comprised of commercial paper and corporate notes and bonds without readily determinable value. The Company reviews trading activity and pricing for these investments as of the measurement date. When sufficient quoted pricing for identical securities is not available, the Company uses market pricing and other observable market inputs for similar securities obtained from various third-party data providers. These inputs either represent quoted prices for similar assets in active markets or have been derived from observable market data. This approach results in the Level 2 classification of these securities within the fair value hierarchy. The Company measures contingent consideration at fair value using a Monte-Carlo simulation utilizing Level 3 inputs. These inputs include the probability of achieving each of the potential milestones, revenue volatility, and an estimated discount rate associated with the risks of the expected cash flows attributable to the achievement of various milestones.

Concentrations and Credit Risk

The Company’s principal financial instruments subject to potential concentration of credit risk are cash and cash equivalents (including restricted cash), and investments, including amounts held in money market funds, commercial paper, and corporate bonds. The Company places cash deposits with a federally insured financial institution. The Company maintains its cash at banks and financial institutions it considers to be of high credit quality; however, the Company’s domestic cash deposits may at times exceed the Federal Deposit Insurance Corporation’s insured limit. Balances in excess of federally insured limitations may not be insured. The Company has not experienced losses on these accounts, and management believes that the Company is not exposed to significant risks on such accounts. Investments are stated at their estimated fair values, based on quoted market prices for the same or similar instruments. The counterparties to the agreements relating to the Company’s investments consist of various major corporations, financial institutions, and government agencies of high credit standing.

The Company’s accounts receivable are derived from sales and leases to customers located throughout the world. The Company evaluates its customers’ financial condition and, generally, requires no collateral from its customers. The Company had one customer that accounted for 69% of the Company’s net accounts receivable as of December 31, 2022. The Company had three customers that accounted for 26%, 20%, and 14%, respectively, of the Company’s net accounts receivable as of December 31, 2021. The Company had one customer who accounted for 47% of revenue in 2022, and two customers who accounted for 36% and 16% of revenue in 2021, respectively.

Accounts Receivable

Accounts receivable are recorded at net realizable value, which includes an allowance for expected credit losses. The allowance for expected credit losses is based on the Company’s assessment of collectability of customer accounts. The Company regularly reviews the allowance by considering factors such as historical experience, credit quality, the age of the accounts receivable balances, and current economic conditions that may affect a customer’s ability to pay. The allowance for expected credit losses was $1.6 million and $1.7 million as of December 31, 2022, and December 31, 2021, respectively. The Company recorded an immaterial amount for expected credit losses during the year ended December 31, 2022 and $0.1 million during the year ended December 31, 2021.

Inventories

Inventories are stated at the lower of cost (determined on a first-in, first-out basis) or net realizable value. Inventory costs include direct materials, direct labor, and normal manufacturing overhead. The Company records reserves, when necessary, to reduce the carrying value of inventory to its net realizable value. Management considers historical consumption and forecast demand in relation to the inventory on hand, competitiveness of product offerings, market conditions and product life cycles when determining excess and obsolescence and net realizable value adjustments. At the point of loss recognition, a new, lower-cost basis for that inventory is established, and any subsequent improvements in facts and circumstances do not result in the restoration or increase in that newly established cost basis.

Any inventory on hand at the measurement date in excess of the Company's current requirements based on anticipated levels of sales is classified as long-term on the Company's consolidated balance sheets. The Company's classification of long-term inventory requires it to estimate the portion of on hand inventory that can be realized over the upcoming twelve months.

Definite-Lived Intangible Assets - Intellectual Property

Intellectual property consists of purchased patent rights and developed technology acquired as part of a business acquisition. Developed technology includes reclassified in-process research and development (“IPR&D”) assets related to (i) the Senhance System acquired in 2015 and reclassified in 2017 and (ii) a 2018 acquisition and reclassified in 2020. Amortization of the patent rights is recorded using the straight-line method over the estimated useful life of the patents of 10 years. Amortization of the developed technology is recorded using the straight-line method over the estimated useful life of 5 to 7 years.

The Company periodically evaluates intellectual property for impairment whenever events or changes in circumstances indicate that the carrying amount may not be recoverable. To determine the recoverability, the Company evaluates the probability that future estimated undiscounted net cash flows will be less than the carrying amount of the assets. If such estimated cash flows are less than the carrying amount of the assets, then such assets are written down to their fair value. No impairment of intellectual property was identified during the years ended December 31, 2022 and 2021.

Property and Equipment

Property and equipment consists primarily of operating lease Senhance System assets, machinery, manufacturing equipment, demonstration equipment, computer equipment, furniture, and leasehold improvements, which are recorded at cost less accumulated depreciation. Depreciation is recorded using the straight-line method over the estimated useful lives of the assets as follows:

Years

Operating lease assets – Senhance System leasing
5

Machinery, manufacturing, and demonstration equipment
3 - 5

Computer equipment
3

Furniture
5

Leasehold improvements

Lesser of lease term or 3 to 10

The Company reviews its property and equipment assets for possible impairment whenever events or changes in circumstances indicate that the carrying amount of the assets may not be fully recoverable. To determine the recoverability of its long-lived assets, the Company evaluates the probability that future estimated undiscounted net cash flows will be less than the carrying amount of the assets. If such estimated cash flows are less than the carrying amount of the long-lived assets, then such assets are written down to their fair value.

During the year ended December 31, 2022, the Company recorded a non-cash asset impairment charge of $1.4 million to reduce the carrying value of property and equipment to its estimated fair value. The property and equipment impairment is associated with returned Senhance Systems under operating leases and Senhance Systems currently under operating leases that are not expected to generate future cash flows sufficient to recover their net book value. The fair value was estimated based on the discounted cash flows expected to be produced by the property and equipment. The impairment was recorded in property and equipment impairment on the consolidated statements of operations and comprehensive loss. No such impairment charges were recorded during the year ended December 31, 2021.

Operating Leases

We have operating leases for our corporate office buildings, vehicles, and machinery and equipment. At inception, we determine whether an agreement represents a lease and, at commencement, we evaluate each lease agreement to determine whether the lease constitutes an operating or financing lease.

The Company accounts for lease components and non-lease components as a single component. Non-lease components consist of common area maintenance payments for most real estate leases, which are determined based on costs incurred by the lessor. Many of the Company’s leases include base rental periods coupled with options to renew or terminate the lease, generally at the Company’s discretion. In evaluating the lease term, the Company considers whether renewal is reasonably certain. To the extent a significant economic incentive exists to renew the lease, the option is included within the lease term. Based on the Company’s leases, renewal options generally do not provide a significant economic incentive and are therefore excluded from the lease term. While our operating leases range from one year to ten years, some may include options to extend the lease generally between one year and six years, and some may include options to terminate the leases within one year.

The interest rate implicit in our lease contracts is typically not readily determinable. As such, we utilize the appropriate incremental borrowing rate, which is the rate incurred to borrow on a collateralized basis over a similar term an amount equal to the lease payments in a similar economic environment. Operating lease expense is recognized on a straight-line basis over the lease term, subject to any changes in the lease or expectations regarding the terms.

Implementation Costs in a Cloud Computing Arrangement

The Company capitalizes qualified implementation costs incurred in a hosting arrangement that is a service contract. These capitalized implementation costs are recorded within other current and long-term assets, and are generally amortized over the fixed, non-cancellable term of the associated hosting arrangement on a straight-line basis and included within operating expenses.

Employee Retention Tax Credit Receivable

The Coronavirus Aid, Relief, and Economic Security Act (the “CARES Act”) included an Employee Retention Tax Credit (“ERTC”) provision designed to encourage employers to keep employees on their payroll. The ERTC is a refundable tax credit against certain payroll taxes paid by employers for eligible wages. During the year ended December 31, 2021, we submitted an ERTC refund for $1.3 million and recorded the amount into Other Income (Expense) on the consolidated statements of operations and comprehensive loss. The Company received notification from the IRS that the relevant conditions of the employee retention credit provision were met and that it will receive the credit. The Company received $0.7 million of the ERTC refund during the year ended December 31, 2022. The remaining $0.6 million is recorded as a current asset on the consolidated balance sheets as of December 31, 2022.

Notes Payable

The Company’s policy is to account for forgivable loans received through the U.S. Small Business Administration (the “SBA”) under the CARES Act Payroll Protection Program (“PPP”), as debt in accordance with ASC 470, Debt, and other related accounting pronouncements. The forgiveness of debt, in whole or part, is recognized once the debt is extinguished, which occurs when the Company is legally released from the liability by the SBA. Any portion of debt forgiven, adjusted for accrued interest forgiven and unamortized debt issuance costs, is recorded as a gain on extinguishment of debt, and presented in the consolidated statements of operations and comprehensive loss. On June 10, 2021, the Company received notification from the SBA that the principal amount of its PPP loan of $2.8 million and related interest had been forgiven.

As of December 31, 2022, the Company has $0.6 million available under a letter of credit. No amounts have been utilized by the Company as of December 31, 2022.

Contingent Consideration

Contingent consideration is recorded as a liability and is the estimate of the fair value of potential milestone payments related to business acquisitions. Contingent consideration is measured at fair value using a Monte-Carlo simulation utilizing significant unobservable inputs including the probability of achieving each of the potential milestones, future Euro-to-USD exchange rates, revenue volatility and an estimated discount rate associated with the risks of the expected cash flows attributable to the various milestones. Significant increases or decreases in any of the probabilities of success or changes in expected achievement of any of these milestones would result in a significantly higher or lower fair value of these milestones, respectively, and commensurate changes to the associated liability. The contingent consideration is revalued at each reporting period and changes in fair value are recognized in the consolidated statements of operations and comprehensive loss.

On September 21, 2015, the Company completed the strategic acquisition, through its wholly owned subsidiary TransEnterix International, from Sofar S.p.A., an Italian company (“Sofar”), an Italian company, of all of the assets, employees and contracts related to the advanced robotic system for minimally invasive laparoscopic surgery now known as the Senhance System. Under the terms of the Purchase Agreement, as amended in 2016, as of December 31, 2022, the Company has accrued $1.3 million of estimated fair value of remaining contingent consideration related to a milestone of €15.0 million which shall be payable upon achievement of trailing revenues from sales or services contracts of the Senhance System of at least €25.0 million over a calendar quarter or in the event that (i) the Company or Asensus International is acquired, (ii) the Company significantly reduces or suspends selling efforts of the Senhance System, or (iii) the Company acquires a business that offers alternative products that are directly competitive with the Senhance System. In 2022, Sofar assigned its right to receive the contingent payment to Three Heads Investment S.r.l.

Warrant Liabilities

The Company’s Series B Warrants were measured at fair value using a simulation model which considered, as of the valuation date, factors including the current exercise price, the expected life of the warrant, the current price of the underlying stock, its expected volatility, holding cost and the risk-free interest rate for the term of the warrant. The warrant liability was revalued at each reporting period and changes in fair value were recognized in the consolidated statements of operations and comprehensive loss. The selection of the appropriate valuation model and the inputs and assumptions that are required to determine the valuation requires significant judgment and requires management to make estimates and assumptions that affect the reported amount of the related liability and reported amounts of the change in fair value. Actual results could differ from those estimates, and changes in these estimates are recorded when known. All remaining outstanding Series B Warrants were exercised in the first quarter 2021.

Revenue Recognition

The Company’s revenue consists of product revenue resulting from the sale of Senhance Systems, Senhance System components, and instruments and accessories. Service revenue consists of revenue related to Senhance System service agreements. Lease revenue consists of revenue generated from utilizing the Senhance System, instruments and accessories, and servicing of the Senhance System under operating lease agreements. The Company accounts for a contract with a customer when there is a legally enforceable contract between the Company and the customer, the rights of the parties are identified, the contract has commercial substance, and collectability of the contract consideration is probable. The Company's revenues are measured based on consideration specified in the contract with each customer, net of any sales incentives and taxes collected from customers that are remitted to government authorities. The Company’s Senhance System sale arrangements generally include a five-year service period; the first year of service is generally free and included in the Senhance System sale arrangement and the remaining four years are generally included at a stated service price.

The Company’s Senhance System sale arrangements generally contain multiple products and services. For these consolidated sale arrangements, the Company accounts for individual products and services as separate performance obligations if they are distinct, which is if a product or service is separately identifiable from other items in the consolidated package, and if a customer can benefit from it on its own or with other resources that are readily available to the customer. The Company’s Senhance System sale arrangements may include a combination of the following performance obligations: system(s), system components, instruments, accessories, and system services.

For arrangements that contain multiple performance obligations, revenue is allocated to each performance obligation based on its relative estimated standalone selling price. When available, standalone selling prices are based on observable prices at which the Company separately sells the products or services; however due to limited sales to date, standalone selling prices generally are not directly observable. The Company estimates the standalone selling price using the market assessment approach considering market conditions and entity-specific factors including, but not limited to, features and functionality of the products and services, geographies, type of customer, and market conditions. The Company regularly reviews estimated standalone selling prices and updates these estimates if necessary.

The Company recognizes revenues when or as the performance obligations are satisfied by transferring control of the product or service to a customer. The Company generally recognizes revenue for the performance obligations as follows:

• System sales. For Senhance Systems and Senhance System components sold directly to end customers (including those arising from Senhance System purchases under lease rights to purchase), revenue is recognized when the Company transfers control to the customer, which is generally at the point when acceptance occurs that indicates customer acknowledgment of delivery or installation, depending on the terms of the arrangement. For lease buyouts, where the customer has already acknowledged installation of the system, transfer of control occurs when the Company receives an executed contract for the lease buyout of the Senhance System. For Senhance Systems sold through distributors, for which distributors are responsible for installation, revenue is recognized generally upon delivery. The Company’s Senhance System arrangements generally do not provide a right of return. The Senhance Systems are generally covered by a one-year warranty. Warranty costs were not material for the periods presented.

• Instruments and accessories. Revenue from sales of instruments and accessories is recognized when control is transferred to the customers, which generally occurs at the time of shipment, but also occurs at the time of delivery depending on the customer arrangement.

• Service. Service revenue is recognized ratably over the term of the service period as the customers benefit from the service throughout the service period. Revenue related to services performed on a time-and-materials basis is recognized when performed.

The Company invoices its customers based on the billing schedules in its sales arrangements. Payments are generally due 30 to 60 days from the date of invoice. Contract assets for the periods presented primarily represent the difference between the revenue that was recognized based on the relative selling price of the related performance obligations and the contractual billing terms in the arrangements, and are included in accounts receivable.

In connection with assets recognized from the costs to obtain a contract with a customer, the Company determined that the sales incentive programs for its sales team do not meet the requirements to be capitalized as the Company does not expect to generate future economic benefits from the related revenue from the initial sales transaction and such costs are expensed as incurred.

Senhance System Leasing

The Company enters into lease arrangements with certain qualified customers. Revenue related to arrangements including lease elements are allocated to lease and non-lease elements based on their relative standalone selling prices. Lease elements generally include a Senhance System, while non-lease elements generally include instruments, accessories, and services. For some lease arrangements, the customers are provided with the right to purchase the leased Senhance System at some point during and/or at the end of the lease term. In some arrangements lease payments are based on the usage of the Senhance System. For the years ended December 31, 2022 and 2021, variable lease revenue related to usage-based arrangements was not material.

In determining whether a transaction should be classified as a sales-type, operating, or direct financing lease, the Company considers the following terms at lease commencement: (1) whether title of the Senhance System transfers automatically or for a nominal fee by the end of the lease term, (2) whether the present value of the minimum lease payments equals or exceeds substantially all of the fair value of the leased Senhance System, (3) whether the lease term is for the major part of the remaining economic life of the leased System, (4) whether the lease grants the lessee an option to purchase the leased Senhance System that the lessee is reasonably certain to exercise, and (5) whether the underlying Senhance System is of such a specialized nature that it is expected to have no alternative use to the Company at the end of the lease term. All such arrangements through December 31, 2022 are classified as operating leases. Revenue related to lease elements from operating lease arrangements is generally recognized on a straight-line basis over the lease term or based upon Senhance System usage. As of December 31, 2022 future minimum lease payments due from customers was $2.2 million, which is expected to be received over the next one to three years.

Cost of Revenue

Cost of revenue consists of contract manufacturing, materials, labor and manufacturing overhead incurred internally to produce the products. Depreciation expense related to leased systems is included in the cost of revenue. Shipping and handling costs incurred by the Company are included in the cost of revenue. We expense all inventory obsolescence provisions as cost of revenue.

Research and Development Costs

Research and development expenses primarily consist of engineering, product development and regulatory expenses, incurred in the design, development, testing and enhancement of our products. Research and development costs are expensed as incurred.

Stock-Based Compensation

The Company recognizes expenses for share-based awards exchanged for services rendered equal to the estimated fair value of these awards over the requisite service period. The Company recognizes as expense, the grant-date fair value of stock options and other stock-based compensation issued to employees and non-employee directors over the requisite service periods, which are typically the vesting periods. The Company uses the Black-Scholes-Merton model to estimate the fair value of stock options. The volatility assumption used in the Black-Scholes-Merton model is based on the Company’s historical volatility. The expected term of options granted has been determined based upon the simplified method, because the Company does not have sufficient historical information regarding its options to derive the expected term. Under this approach, the expected term is the mid-point between the weighted average of vesting period and the contractual term. The risk-free interest rate is based on U.S. Treasury rates whose term is consistent with the expected life of the stock options. The Company has not paid and does not anticipate paying cash dividends on its shares of common stock; therefore, the expected dividend yield is assumed to be zero. The Company estimates forfeitures based on its historical experience and adjust the estimated forfeiture rate based upon actual experience. For performance-based restricted stock awards with performance conditions, we begin recognizing compensation expense when it becomes probable that the performance condition will be attained.

The fair value of restricted stock units is determined by the market price of the Company’s common stock on the date of grant. See “Note 13 – Stock-Based Compensation,” for a detailed discussion of the Company’s stock plans and stock-based compensation expense.

Income Taxes

The Company accounts for income taxes using the asset and liability method, which requires the recognition of deferred tax assets or liabilities for the temporary differences between financial reporting and tax basis of the Company’s assets and liabilities, and for tax carryforwards at enacted statutory rates in effect for the years in which the asset or liability is expected to be realized. The effect on deferred taxes of a change in tax rates is recognized in income during the period that includes the enactment date. In addition, valuation allowances are established when necessary to reduce deferred tax assets and liabilities to the amounts expected to be realized. The Company has elected to account for global intangible low-taxed income (“GILTI”) as a period expense in the year the tax is incurred.

The Company recognizes the financial statement benefit of an income tax position only after determining that the relevant taxing authority would more likely than not sustain the position following audit. For tax positions meeting the more likely than not threshold, the amount recognized in the financial statements is the largest benefit that has a greater than 50% likelihood of being realized upon ultimate settlement with the relevant taxing authority. The Company recognizes interest accrued related to unrecognized tax benefits and penalties in the provision for income taxes.

Tax regulations within each jurisdiction are subject to the interpretation of the related tax laws and regulations and require application of significant judgment. The Company is subject to U.S. federal and various state, local and foreign jurisdictions. Due to the Company’s net operating loss carryforwards, the Company may be subject to examination by authorities for all previously filed income tax returns.

Comprehensive Loss

Comprehensive loss is defined as the change in equity of a business enterprise during a period from transactions and other events and circumstances from non-owner sources.

Segments

The Company operates in one business segment—the research, development and sale of medical device robotics to improve minimally invasive surgery. The Company’s chief operating decision maker (determined to be the Chief Executive Officer) does not manage any part of the Company separately, and the allocation of resources and assessment of performance are based on the Company’s consolidated operating results.

Impact of Recently Issued Accounting Standards

The Company has evaluated issued ASUs not yet adopted and believes the adoption of these standards will not have a material impact on its consolidated financial statements.

Note 12 - Income Taxes - Unrecognized Tax Positions (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Beginning balance	$ 141	$ 0
Gross increases for tax positions related to current periods	194	141
Gross decreases related to 382 limitations	0	0
Ending balance	$ 335	$ 141

Note 4 - Cash, Cash Equivalents, and Restricted Cash (Tables)

12 Months Ended

Dec. 31, 2022

Schedule of Cash, Cash Equivalents, and Restricted Cash [Table Text Block]

	December 31,		December 31,
	2022		2021
	(in thousands)
Cash	$	3,473	$	8,343
Money Market		2,856		5,287
Commerical Paper		-		4,499
Total cash and cash equivalents	$	6,329	$	18,129
Restricted Cash		1,141		1,154
Total	$	7,470	$	19,283

Note 13 - Stock-based Compensation - Non-cash Share-based Compensation Expense (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Share-based compensation	$ 8,416	$ 9,429
Share-Based Payment Arrangement, Option [Member]
Share-based compensation	3,654	4,535
Restricted Stock Units (RSUs) [Member]
Share-based compensation	3,319	3,954
Performance Restricted Stock Unit [Member]
Share-based compensation	$ 1,443	$ 940

Note 4 - Cash, Cash Equivalents, and Restricted Cash - Cash, Cash Equivalents, and Restricted Cash (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Cash	$ 3,473	$ 8,343
Money Market	2,856	5,287
Commerical Paper	0	4,499
Total cash and cash equivalents	6,329	18,129
Restricted Cash and Cash Equivalents, Noncurrent, Total	1,141	1,154
Total	$ 7,470	$ 19,283

Note 8 - Property and Equipment (Tables)

12 Months Ended

Dec. 31, 2022

Property, Plant and Equipment [Table Text Block]

	December 31, 2022			December 31, 2021
	(In thousands)
Machinery, manufacturing, and demonstration equipment	$	8,450		$	8,289
Operating lease assets - Senhance System leasing		10,251			10,143
Computer equipment		600			325
Furniture		831			644
Leasehold improvements		1,654			1,259
Construction in process		436		‑
Total property and equipment		22,222			20,660
Accumulated depreciation and amortization		(12,680	)		(9,689	)
Property and equipment, net	$	9,542		$	10,971

Note 12 - Income Taxes - Income Tax Expense (Benefit) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Federal	$ 0	$ 0
State	0	0
Foreign	239	232
Federal	0	0
State	0	0
Foreign	79	(7)
Total income tax expense	$ 318	$ 225

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References + Details

Note 13 - Stock-based Compensation

12 Months Ended

Dec. 31, 2022

Share-Based Payment Arrangement [Text Block]

13.

Stock-Based Compensation

Overview

On July 22, 2021, at the 2021 Annual Meeting of Stockholders, stockholders voted to approve the Company’s Amended and Restated Incentive Compensation Plan (the “Plan”) to increase the number of shares reserved for issuance under the Plan by 22,000,000 shares. As of December 31, 2022, there were 32,072,308 shares authorized for issuance, and 11,038,824 shares available for future issuance under the Plan. To date all equity awards under the Plan have consisted of nonqualified stock options, incentive stock options, and restricted stock units.

Under the Plan, which is administered by the Compensation Committee, the Company may grant stock options, stock appreciation rights, restricted stock and/or deferred stock to employees, officers, directors, consultants, and vendors. The exercise price of stock options or stock appreciation rights may not be less than the fair market value of the Company’s shares at the date of grant. Additionally, no stock options or stock appreciation rights granted under the Plan may have a term exceeding ten years.

Stock Options

The following table summarizes the Company’s stock option activity, including grants to non-employees, for the year ended December 31, 2022:

	Number of Shares			Weighted- Average Exercise Price		Weighted-Average Remaining Contractual Term (Years)
Balance at December 31, 2021		4,640,660		$	6.64		5.66
Granted		3,153,881			0.70
Forfeited		(129,134	)		1.60
Cancelled		(36,987	)		21.11
Exercised		(43,453	)		0.41
Balance at December 31, 2022		7,584,967		$	4.22		5.31

The aggregate intrinsic value of stock options exercised under the Company’s stock plans was not material during the year ended December 31, 2022.

The following table summarizes information about stock options outstanding at December 31, 2022:

Number of

Shares

Weighted-

Average Exercise

Price

Weighted-Average

Remaining

Contractual Term

(Years)

Aggregate

Intrinsic Value

(Millions)

Exercisable at December 31, 2022

3,524,473

7.40

4.75

Vested or expected to vest at December 31, 2022

7,350,141

4.32

5.28

The fair value of options granted were estimated using the Black-Scholes-Merton option pricing model based on the assumptions in the table below:

	Years Ended December 31,
	2022			2021
Expected dividend yield	0%			0%
Expected volatility	126%	-	133%	118%	-	139%
Risk-free interest rate	1.25%	-	4.40%	0.33%	-	1.11%
Expected life (in years)	3.8	-	4.5	3.8	-	4.5

Restricted Stock Units

The following is a summary of the restricted stock units activity, including performance restricted stock units, for the year ended December 31, 2022:

	Number of Restricted Stock Units Outstanding			Weighted- Average Grant Date Fair Value
Unvested December 31, 2021		3,839,030		$	2.36
Granted		6,996,822			0.71
Vested		(2,076,663	)		2.34
Forfeited		(275,698	)		1.19
Unvested December 31, 2022		8,483,491		$	1.04

Performance Restricted Stock Units

In 2022 and 2021, the Company granted performance-based restricted stock units with vesting terms based on our attainment of certain operational targets by October 1, 2023 and October 1, 2022, respectively. The number of shares earnable under the 2022 and 2021 awards are based on achieving designated corporate goals. These operational targets were achieved for 2022 and 2021, therefore the performance-based restricted stock units are fully earned and remain subject to three-year time-based vesting requirements.

Stock-based Compensation Expense

The following table summarizes non-cash stock-based compensation expense by award type for the years ended December 31, 2022, and 2021:

	Years Ended December 31,
	2022		2021
	(in thousands)
Stock options	$	3,654	$	4,535
Restricted stock units		3,319		3,954
Performance restricted stock units		1,443		940
	$	8,416	$	9,429

As of December 31, 2022, the Company had future employee stock-based compensation expense of approximately $2.1 million related to unvested stock options, which is expected to be recognized over an estimated weighted-average period of 1.5 years. As of December 31, 2022, the unrecognized stock-based compensation expense related to unvested restricted stock units and performance restricted stock units was approximately $4.2 million, which is expected to be recognized over a weighted average period of approximately 1.4 years.

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Current Assets:
Cash and cash equivalents	$ 6,329	$ 18,129
Short-term investments, available-for-sale	64,195	80,262
Accounts receivable, net	2,256	749
Inventories	8,284	8,634
Prepaid expenses	3,584	3,255
Employee retention tax credit receivable	554	1,311
Other current assets	1,671	957
Total Current Assets	86,873	113,297
Restricted cash	1,141	1,154
Long-term investments, available-for-sale	3,865	37,435
Inventories, net of current portion	5,469	7,074
Property and equipment, net	9,542	10,971
Intellectual property, net	1,576	9,892
Net deferred tax assets	174	288
Operating lease right-of-use assets, net	4,950	5,348
Other long-term assets	2,463	1,014
Total Assets	116,053	186,473
Current Liabilities:
Accounts payable	3,348	3,448
Accrued employee compensation and benefits	4,508	3,559
Accrued expenses and other current liabilities	1,293	1,617
Operating lease liabilities - current portion	800	683
Deferred revenue	465	543
Total Current Liabilities	10,414	9,850
Long-Term Liabilities:
Contingent consideration	1,256	2,371
Noncurrent operating lease liabilities	4,738	5,006
Total Liabilities	16,408	17,227
Commitments and Contingencies (Note 16)
Stockholders' Equity:
Common stock $0.001 par value, 750,000,000 shares authorized at December 31, 2022 and December 31, 2021; 236,895,440 and 235,218,552 shares issued and outstanding at December 31, 2022 and December 31, 2021, respectively	237	235
Preferred stock, $0.01 par value, 25,000,000 shares authorized, no shares issued and outstanding at December 31, 2022 and December 31, 2021	0	0
Additional paid-in capital	962,731	954,649
Accumulated deficit	(860,935)	(785,374)
Accumulated other comprehensive loss	(2,388)	(264)
Total Stockholders' Equity	99,645	169,246
Total Liabilities and Stockholders' Equity	116,053	186,473
Intellectual Property [Member]
Current Assets:
Intellectual property, net	$ 1,576	$ 9,892

Note 11 - Accrued Expenses - Components of Accrued Expenses (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Consulting and other vendors	$ 155	$ 128
Other	0	124
Royalties	24	247
Legal and professional fees	275	503
Taxes and other assessments	839	615
Total	$ 1,293	$ 1,617

Note 13 - Stock-based Compensation - Stock Options Outstanding (Details) $ / shares in Units, $ in Millions	12 Months Ended
	Dec. 31, 2022 USD ($) $ / shares shares
Options, Exercisable, Number of Shares (in shares) \| shares	3,524,473
Options, Exercisable, Weighted Average Exercise Price (in dollars per share) \| $ / shares (in dollars per share) \| $ / shares	$ 7.40
Options, Exercisable, Weighted Average Remaining Contractual Term (Year)	4 years 9 months
Options, Exercisable, Aggregate Intrinsic Value \| $	$ 0
Options, Vested and Expected to Vest, Exercisable, Number of Shares (in shares) \| shares	7,350,141
Options, Vested and Expected to Vest, Exercisable, Weighted Average Exercise Price (in dollars per share) \| $ / shares	$ 4.32
Options, Vested and Expected to Vest, Exercisable, Weighted Average Remaining Contractual Term (Year)	5 years 3 months 10 days
Options, Vested or Expected to Vest, Aggregate Intrinsic Value \| $	$ 0

Note 7 - Inventories (Tables)

12 Months Ended

Dec. 31, 2022

Schedule of Inventory, Current [Table Text Block]

	December 31, 2022
	(in thousands)
	Gross Carrying Amount		Reserve Balance			Net Carrying Amount
Finished goods	$	15,337	$	(4,129	)	$	11,208
Raw materials		4,718		(2,173	)		2,545
Total inventories	$	20,055	$	(6,302	)	$	13,753

Current Portion	$	9,399	$	(1,115	)	$	8,284
Long-term portion		10,656		(5,187	)		5,469
Total inventories	$	20,055	$	(6,302	)	$	13,753

	December 31, 2021
	(in thousands)
	Gross Carrying Amount		Reserve Balance			Net Carrying Amount
Finished goods	$	13,066	$	(2,987	)	$	10,079
Raw materials		8,324		(2,695	)		5,629
Total inventories	$	21,390	$	(5,682	)	$	15,708

Current Portion	$	9,931	$	(1,297	)	$	8,634
Long-term portion		11,459		(4,385	)		7,074
Total inventories	$	21,390	$	(5,682	)	$	15,708

Note 10 - Leases -Supplemental Balance Sheet Information (Details)	Dec. 31, 2022	Dec. 31, 2021
Weighted-average remaining lease term (in years) (Year)	6 years 9 months 18 days	7 years 9 months 18 days
Weighted-average discount rate	8.40%	7.80%
Minimum [Member]
Incremental borrowing rate	6.10%	6.10%
Maximum [Member]
Incremental borrowing rate	14.50%	8.50%

Note 4 - Cash, Cash Equivalents, and Restricted Cash (Details Textual) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Restricted Cash and Cash Equivalents, Noncurrent, Total	$ 1,141	$ 1,154

Note 14 - Equity Offerings

12 Months Ended

Dec. 31, 2022

Stockholders' Equity Note Disclosure [Text Block]

14.

Equity Offerings

Equity financing transactions for the years ended December 31, 2022 and 2021, include:

2020 ATM Offering. On October 9, 2020, the Company filed a prospectus supplement relating to an at-the-market offering with Cantor pursuant to which the Company could sell from time to time, at its option, up to an aggregate of $40.0 million of shares of the Company’s common stock (the “2020 ATM Offering”). The Company terminated this agreement in January 2021.

January 2021 Public Offering. On January 29, 2021, the Company completed an underwritten public offering of 26,545,832 shares of its common stock, including the underwriter’s full exercise of an over-allotment option on February 1, 2021, at the public offering price of $3.00 per share, generating net proceeds of approximately $73.4 million.

January 2021 Registered Direct Purchase Agreement. On January 12, 2021, the Company sold in a registered direct offering 25,000,000 shares of common stock at a purchase price per share of $1.25 for aggregate net proceeds of $28.6 million.

2021 ATM Offering. On May 19, 2021, we entered into a Controlled Equity Offering^SM Sales Agreement with Cantor, Robert W. Baird & Co. Incorporated and Oppenheimer & Co. Inc., as our sales agents, relating to an at-the-market offering of up to an aggregate of $100,000,000 of shares of our common stock, referred to as the “2021 ATM Offering”.

Sales during the year ended December 31, 2021, under the 2021 and 2020 ATM Offering are as follows (in thousands, except for share and per share amounts):

	Year Ended December 31, 2021

Total shares of common stock sold		20,237,045
Average price per share	$	1.53
Gross proceeds	$	30,943
Commisssion earned by Sales Agents	$	928
Net proceeds	$	30,015

2021 Exercise of Warrants. During the year ended December 31, 2021, certain holders of our Series B, C and D warrants to purchase shares of our common stock exercised such warrants for aggregate proceeds to the Company of $30.6 million.

2022 ATM Offering. On March 18, 2022, the Company entered a Controlled Equity Offering Sales Agreement (the “2022 Sales Agreement”), with Cantor Fitzgerald & Co., and Oppenheimer & Co. Inc. The Company commenced an at-the-market offering (the “2022 ATM Offering”) pursuant to which the Company could sell from time to time, at its option, up to an aggregate of $100.0 million shares of the Company’s common stock. No sales of common stock were made under the 2022 ATM Offering during the year ended December 31, 2022.

The entire disclosure for shareholders' equity comprised of portions attributable to the parent entity and noncontrolling interest, including other comprehensive income. Includes, but is not limited to, balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings, accumulated balance for each classification of other comprehensive income and amount of comprehensive income.

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-URI https://asc.fasb.org/extlink&oid=126973232&loc=SL123496180-112644

Reference 14: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 13
-Subparagraph (i)
-URI https://asc.fasb.org/extlink&oid=126973232&loc=SL123496158-112644

Reference 15: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(e)(1))
-URI https://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

Reference 16: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 40
-Section 50
-Paragraph 6
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126731327&loc=SL126733271-114008

Note 2 - Summary of Significant Accounting Policies - Estimated Useful Lives of Assets (Details)	12 Months Ended
	Dec. 31, 2022
Operating Lease Assets [Member]
Property and equipment, estimated useful lives (Year)	5 years
Machinery, Manufacturing and Demonstration Equipment [Member] \| Minimum [Member]
Property and equipment, estimated useful lives (Year)	3 years
Machinery, Manufacturing and Demonstration Equipment [Member] \| Maximum [Member]
Property and equipment, estimated useful lives (Year)	5 years
Computer Equipment [Member]
Property and equipment, estimated useful lives (Year)	3 years
Furniture and Fixtures [Member]
Property and equipment, estimated useful lives (Year)	5 years
Leasehold Improvements [Member] \| Minimum [Member]
Property and equipment, estimated useful lives (Year)	3 years
Leasehold Improvements [Member] \| Maximum [Member]
Property and equipment, estimated useful lives (Year)	10 years

Note 14 - Equity Offerings - Summary of Sales Under Offering (Details) - The 2021 and 2020 ATM Offering [Member] $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2021 USD ($) $ / shares shares
Total shares of common stock sold (in shares) \| shares	20,237,045
Average price per share (in dollars per share) \| $ / shares	$ 1.53
Gross proceeds	$ 30,943
Commisssion earned by Sales Agents	928
Net proceeds	$ 30,015

Note 3 - Revenue Recognition (Tables)

12 Months Ended

Dec. 31, 2022

Disaggregation of Revenue [Table Text Block]

	Years Ended December 31,
	2022		2021
	(in thousands)
U.S.
Systems	$	-	$	-
Instruments and accessories		211		273
Services		300		383
Leases		256		377
Total U.S. revenue		767		1,033

Outside of U.S. ("OUS")
Systems		2,551		3,286
Instruments and accessories		1,565		1,840
Services		1,073		1,137
Leases		1,131		936
Total OUS revenue		6,320		7,199

Total
Systems		2,551		3,286
Instruments and accessories		1,776		2,113
Services		1,373		1,520
Leases		1,387		1,313
Total revenue	$	7,087	$	8,232

Contract with Customer, Contract Asset, Contract Liability, and Receivable [Table Text Block]

	December 31, 2022		December 31, 2021
	(in thousands)
Contract Assets	$	116	$	91
Deferred Revenue	$	465	$	543

Consolidated Statements of Operations and Comprehensive Loss - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Revenue:
Revenue	$ 7,087	$ 8,232
Cost of revenue:
Cost of revenue	10,872	11,096
Gross loss	(3,785)	(2,864)
Operating Expenses:
Research and development	28,942	19,348
Sales and marketing	14,756	13,395
General and administrative	20,172	19,323
Amortization of intangible assets	7,708	11,254
Change in fair value of contingent consideration	(1,115)	(1,565)
Property and equipment impairment	1,431	0
Total Operating Expenses	71,894	61,755
Operating Loss	(75,679)	(64,619)
Other Income (Expense), net
Gain on extinguishment of debt	0	2,847
Change in fair value of warrant liabilities	0	(1,981)
Interest income	1,141	590
Interest expense	(410)	(370)
Employee retention tax credit	0	1,311
Other expense, net	(295)	(15)
Total Other Income (Expense), net	436	2,382
Loss before income taxes	(75,243)	(62,237)
Income tax expense	(318)	(225)
Net loss	(75,561)	(62,462)
Comprehensive loss:
Net loss	(75,561)	(62,462)
Foreign currency translation loss	(1,867)	(2,985)
Unrealized loss on available-for-sale investments	(257)	(247)
Comprehensive loss	$ (77,685)	$ (65,694)
Net loss per common share attributable to common stockholders - basic and diluted (in dollars per share)	$ (0.32)	$ (0.28)
Weighted average number of shares used in computing net loss per common share - basic and diluted (in shares)	236,492	226,960
Product [Member]
Revenue:
Revenue	$ 4,327	$ 5,399
Cost of revenue:
Cost of revenue	5,303	5,741
Service [Member]
Revenue:
Revenue	1,373	1,520
Cost of revenue:
Cost of revenue	2,174	1,799
Lease [Member]
Revenue:
Revenue	1,387	1,313
Cost of revenue:
Cost of revenue	$ 3,395	$ 3,556

Note 12 - Income Taxes (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount	$ 16,400
Unrecognized Tax Benefits, Ending Balance	335	$ 141	$ 0
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued, Total	$ 0	$ 0
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	21.00%	21.00%
Domestic Tax Authority [Member]
Increase (Decrease) in Operating Loss Carryforwards	$ (253,000)
Operating Loss Carryforwards	419,400
Operating Loss Carryforwards, Subject to Expiration	254,500
Operating Loss Carryforwards, Not Subject to Expiration	164,900
Domestic Tax Authority [Member] \| Research Tax Credit Carryforward [Member]
Tax Credit Carryforward, Amount	10,200
Increase (Decrease) in Tax Credit Carryforward	(8,800)
Domestic Tax Authority [Member] \| Impact of 382 Ownership Changes [Member]
Increase (Decrease) in Operating Loss Carryforwards	(253,000)
State and Local Jurisdiction [Member]
Operating Loss Carryforwards	328,900
Operating Loss Carryforwards, Subject to Expiration	317,400
Operating Loss Carryforwards, Not Subject to Expiration	11,500
State and Local Jurisdiction [Member] \| Impact of 382 Ownership Changes [Member]
Increase (Decrease) in Operating Loss Carryforwards	(204,000)
Foreign Tax Authority [Member] \| Ministry of Economic Affairs and Finance, Italy [Member]
Operating Loss Carryforwards	24,600
Foreign Tax Authority [Member] \| Luxembourg Inland Revenue [Member]
Operating Loss Carryforwards, Subject to Expiration	95,900
Foreign Tax Authority [Member] \| Swiss Federal Tax Administration (FTA) [Member]
Operating Loss Carryforwards, Subject to Expiration	116,500
Foreign Tax Authority [Member] \| Canada Revenue Agency [Member]
Operating Loss Carryforwards, Subject to Expiration	$ 900

Note 5 - Investments, Available-for-sale (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Proceeds from Sale of Debt Securities, Available-for-Sale	$ 0	$ 0
Debt Securities, Available-for-Sale, Realized Gain (Loss), Total	$ 0	$ 0

Note 17 - Segments and Geographic Areas (Tables)

12 Months Ended

Dec. 31, 2022