| Summary of Significant Accounting Policies | Summary of Significant Accounting Policies Principles of Consolidation The accompanying consolidated financial statements include the accounts of the Company and its wholly owned subsidiaries. All intercompany balances and transactions have been eliminated upon consolidation. Use of Estimates The preparation of consolidated financial statements in conformity with accounting principles generally accepted in the United States of America requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the consolidated financial statements and the reported amounts of expenses during the reporting period. Significant estimates and assumptions made in the accompanying consolidated financial statements include, but are not limited to the valuation of inventory, goodwill and intangible assets, the allowance for doubtful accounts, recoverability of the Company’s net deferred tax assets, and related valuation allowance amounts and certain accruals. The Company evaluates its estimates and assumptions on an ongoing basis using historical experience and other factors and adjusts those estimates and assumptions when facts and circumstances dictate. Actual results could materially differ from those estimates . Cash, Cash Equivalents and Restricted Cash The Company considers all highly liquid investments purchased with original maturities of three months or less from the purchase date to be cash equivalents. Cash equivalents consist primarily of amounts invested in money market accounts. The following table provides a reconciliation of cash, cash equivalents, and restricted cash reported within the consolidated statements of cash flows: December 31, 2023 2022 (in thousands) Cash and cash equivalents $ 328,422 $ 156,586 Restricted cash 1,404 1,716 Total cash, cash equivalents, and restricted cash $ 329,826 $ 158,302 Restricted cash as of December 31, 2023 and 2022 relates to corporate credit card security, customer bank guarantee security, and letters of credit established for the real estate property leases relating to the Company’s office buildings, and is recorded as other assets on the consolidated balance sheets. Short-Term Investments Short-term investments have been classified as available-for-sale and are carried at estimated fair value as determined based upon quoted market prices or pricing models for similar securities. The Company determines the appropriate classification of its investments in debt securities at the time of purchase. Available-for-sale securities with original maturities beyond three months at the date of purchase are classified as current based on their availability for use in current operations. As the Company may sell its securities at any time for use in current operations even if the securities have not yet reached maturity, all marketable securities are classified as current assets in the Company’s consolidated balance sheets. The Company evaluates, on a quarterly basis, its marketable securities for potential impairment. For marketable securities in an unrealized loss position, the Company assesses whether such declines are due to credit loss based on factors such as changes to the rating of the security by a ratings agency, market conditions and supportable forecasts of economic and market conditions, among others. If credit loss exists, the Company assess whether it has plans to sell the security or it is more likely than not it will be required to sell any marketable security before recovery of its amortized cost basis. If either condition is met, the security’s amortized cost basis is written down to fair value and is recognized through other income, net. The Company has not identified any such impairment losses to date. If neither condition is met, declines as a result of credit losses, if any, are recognized as an allowance for credit loss, limited to the amount of unrealized loss, through other income, net. Any portion of unrealized loss that is not a result of a credit loss, is recognized in other comprehensive income. Realized gains and losses, if any, on marketable securities are included in other income, net. The cost of investments sold is based on the specific-identification method. Interest on marketable securities is included in other income, net. The Company elected to present accrued interest receivable separately from short-term and long-term investments on its consolidated balance sheets. Accrued interest receivable was recorded in prepaid expenses and other current assets as of December 31, 2023 and 2022. The Company also elected to exclude accrued interest receivable from the estimation of expected credit losses on its marketable securities and reverse accrued interest receivable through interest income (expense) when amounts are determined to be uncollectible. The Company did not write off any accrued interest receivable during the year ended December 31, 2023, 2022, and 2021. Equity Method Investments Entities for which the Company has significant influence over the activities of the entity, but does not control, are accounted for under the equity method of accounting in accordance with ASC 323, Investments - Equity Method and Joint Ventures ( “ ASC 323 ” ) . The Company’s carrying value in the equity method investment is reported as equity method investment on the Company’s consolidated balance sheets. The Company records its proportionate share of the underlying income or loss which is recognized in earnings or loss from the equity method investment. T he Company eliminates a portion of intra-entity profit to the extent the goods sold by the Company have not yet been sold through by the equity method investee to an end customer at the end of the reporting period. The profit earned by the Company from the equity method investee for items not yet sold through is eliminated through equity method earnings or loss which is recognized in income (loss) from equity method investment. The Company assesses its equity method investment for impairment when events or circumstances suggest that the carrying amount of the investment may be impaired. The Company considers all available evidence in assessing whether a decline in fair value is other than temporary. If the decline in fair value is determined to be other than temporary, the difference between the carrying amount of the investment and estimated fair value is recognized as an impairment charge. The Company has not identified any such impairment losses to date. Concentration of Credit Risk Financial instruments that potentially subject the Company to significant concentrations of credit risk consist primarily of cash, cash equivalents, restricted cash, investments and trade receivables. Risks associated with cash, cash equivalents and restricted cash are mitigated by banking with creditworthy institutions and purchasing investments with investment grade ratings. The Company performs ongoing evaluations of its customers using its historical collection experience, current and future economic market conditions and a review of the current aging status and financial condition of its customers, and generally does not require collateral. Concentration of Customers For the years ended December 31, 2023, 2022 and 2021 no customer accounted for 10% or more of the Company’s revenue. There were no customers which accounted for 10% or more of the Company’s accounts receivable as of December 31, 2023 and 2022. Fair Value of Financial Instruments The Company’s cash and cash equivalents, restricted cash, short-term investments, accounts receivable, accounts payable and accrued liabilities approximate their fair value due to their short maturities. The Company utilizes valuation techniques that maximize the use of observable inputs and minimize the use of unobservable inputs to the extent possible. The Company determines the fair value of its financial instruments based on assumptions that market participants would use in pricing an asset or liability in the principal or most advantageous market. When considering market participant assumptions in fair value measurements, the following fair value hierarchy distinguishes between observable and unobservable inputs, which are categorized in one of the following levels: Level 1 – Inputs are unadjusted, quoted prices in active markets for identical assets or liabilities at the measurement date; Level 2 – Inputs are observable, unadjusted quoted prices in active markets for similar assets or liabilities, unadjusted quoted prices for identical or similar assets or liabilities in markets that are not active or other inputs that are observable or can be corroborated by observable market data for substantially the full term of the related assets or liabilities; and Level 3 – Unobservable inputs that are significant to the measurement of the fair value of the assets or liabilities that are supported by little or no market data. Accounts Receivable and Allowance for Doubtful Accounts Accounts receivable are recorded at invoice value, net of any allowance for credit losses. The Company’s expected loss allowance methodology for receivables is developed using its historical collection experience, current and future economic market conditions and a review of the current aging status and financial condition of its customers. Specific allowance amounts are established to record the appropriate allowance for customers that have an identified risk of default. General allowance amounts are established based upon the Company’s assessment of expected credit losses for its receivables by aging category. Balances are written off when they are ultimately determined to be uncollectible. The following table summarizes the activity in the allowance for doubtful accounts: For the Year Ended December 31, 2023 2022 2021 (in thousands) Beginning balance $ 710 $ 350 $ 380 Amounts charged (reversed) to costs and expenses 1,479 364 (12) Write-offs (10) (4) (18) Ending balance $ 2,179 $ 710 $ 350 Inventory Inventory is stated at the lower of standard cost (which approximates actual cost on a first-in, first-out basis) and net realizable value. Inventory costs include direct materials, direct labor and normal manufacturing overhead. Prior to achieving normal capacity, excess capacity costs are expensed in cost of product revenue as period costs. Finished goods that are used for research and development are expensed as consumed. Provisions for slow-moving, excess or obsolete inventories are recorded when required to reduce inventory values to their estimated net realizable values based on product life cycle, development plans, product expiration or quality issues. Property, Plant, and Equipment Property and equipment are stated at cost, net of accumulated depreciation and amortization. Land is carried at cost. Depreciation and amortization (other than land, which is not depreciated) is computed using the straight-line method over the estimated useful lives of the respective assets: Asset Category Useful Life Equipment 3 - 5 years Office Furniture 5 years Software 3 years Building 25 years Leasehold Improvement Lesser of useful life or remaining lease term When assets are retired or otherwise disposed of, the cost and related accumulated depreciation and amortization are removed from the balance sheets and any resulting gain or loss is reflected in operations in the period realized. Maintenance and repairs are charged to operations as incurred. Impairment of Long-Lived Assets The Company reviews long-lived assets for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. Recoverability is measured by comparing the carrying amount to the future net undiscounted cash flows which the assets are expected to generate. If such assets are considered to be impaired, the impairment to be recognized is measured by the amount by which the carrying amount of the assets exceeds the projected discounted future net cash flows arising from the asset. The Company has not identified any such impairment losses to date. Revenue To determine revenue recognition for arrangements that an entity determines are within the scope of ASC 606, Revenue from Contracts with Customers ( “ ASC 606 ” ) , the Company performs the following five steps: (i) identify the contract(s) with a customer; (ii) identify the performance obligations in the contract; (iii) determine the transaction price; (iv) allocate the transaction price to the performance obligations in the contract; and (v) recognize revenue when (or as) the entity satisfies a performance obligation. Product Revenue The Company records product revenue primarily from the sale of its IVL catheters and Reducer. The Company sells its products to hospitals, primarily through direct sales, as well as through distributors in selected international markets. Product revenue is recognized when a customer obtains control of promised goods, in an amount that reflects the consideration which the Company expects to receive in exchange for those goods. For products sold through direct sales and distributors internationally, control is transferred based on the contractual or standard shipping terms. The Company has elected to account for shipping and handling activities that occur after the customer has obtained control as a fulfillment activity, and not a separate performance obligation. The Company may provide for the use of an IVL generator and connector cable under an agreement to customers at no charge to facilitate the use of the IVL catheters. These agreements generally do not contain contractually enforceable minimum commitments and are generally cancellable by either party with 30 days’ notice. License Revenue For arrangements that contain a license of the Company’s functional intellectual property with a customer, the Company considers whether the license grant is distinct from other performance obligations in the arrangement. A license grant of functional intellectual property is generally considered to be capable of being distinct if a customer can benefit from the license on its own or together with other readily available resources. License revenue for licenses of functional intellectual property is recognized at a point in time when the Company satisfies its performance obligation of transferring the license to the customer. Consideration received in advance of the satisfaction of a performance obligation is recognized as a contract liability. No license revenues have been recognized for the years ended December 31, 2023, 2022, and 2021. Research and Development Costs Research and development costs, including new product development, regulatory compliance, and clinical research are expensed as incurred. Accrued Research and Development Costs The Company accrues liabilities for estimated costs of research and development activities conducted by its third-party service providers, which include the conduct of preclinical and clinical studies. The estimated costs of research and development activities are recorded based upon the estimated amount of services provided but not yet invoiced, and these costs are included in accrued liabilities on the consolidated balance sheets and within research and development expense on the consolidated statements of operations and comprehensive loss. These costs are accrued for based on factors such as estimates of the work completed and budget provided and in accordance with agreements established with third-party service providers. Significant judgments and estimates are made in determining the accrued liabilities balance in each reporting period. Accrued liabilities are adjusted as actual costs become known. There have not been any material differences between accrued costs and actual costs incurred since the Company’s inception. Stock-Based Compensation The Company accounts for share-based payments at fair value. The fair value of stock options is measured using the Black-Scholes option-pricing model. For share-based awards that vest subject to the satisfaction of a service requirement, the fair value measurement date for stock-based compensation awards is the date of grant and the expense is recognized on a straight-line basis, over the vesting period. For share-based awards that vest upon the satisfaction of a performance target, the related compensation cost is recognized over the requisite service period based on the expected achievement of the performance target. The Company accounts for forfeitures as they occur. Leases The Company determines if an arrangement is or contains a lease at contract inception by assessing whether the arrangement contains an identified asset and whether the lessee has the right to control such asset. The Company is required to classify leases as either finance or operating leases and to record a right-of-use asset and a lease liability for all leases with a term greater than 12 months regardless of the lease classification. The lease classification will determine whether the lease expense is recognized based on an effective interest rate method or on a straight-line basis over the term of the lease. The Company determines the initial classification and measurement of its right-of-use assets and lease liabilities at the lease commencement date and thereafter, if modified. The Company does not have material finance leases. For its operating leases with a lease term of 12 months or greater, the Company recognized a right-of-use asset and a lease liability on its consolidated balance sheets. The lease liability is determined as the present value of future lease payments using an estimated rate of interest that the Company would have to pay to borrow equivalent funds on a collateralized basis at the lease commencement date. The right-of-use asset is based on the liability adjusted for any prepaid or deferred rent. The lease term at the commencement date is determined by considering whether renewal options and termination options are reasonably assured of exercise. Operating lease cost for the operating lease is recognized on a straight-line basis over the lease term and is included in operating expenses on the consolidated statements of operations and comprehensive loss. Lease payments may be fixed or variable; however, only fixed payments are included in the Company’s lease liability calculation. Lease costs for the Company’s operating leases are recognized on a straight-line basis within operating expenses over the lease term. The Company’s lease agreements may contain variable non-lease components such as common area maintenance, operating expenses or other costs, which are expensed as incurred. The Company elected the practical expedients to exclude from its balance sheets recognition of leases having a term of 12 months or less (short-term leases) and to not separate lease components and non-lease components for its long-term real estate leases. Defined Contribution Plan The Company has a defined contribution retirement savings plan under Section 401(k) of the Internal Revenue Code of 1986, as amended. This plan allows eligible employees to defer a portion of their annual compensation on a pre-tax basis. The Company recognized expense related to its contributions to the plan of $5.3 million, $3.7 million, and $2.5 million for the years ended December 31, 2023, 2022, and 2021, respectively. Comprehensive Income (Loss) Comprehensive income (loss) is comprised of net loss and changes in unrealized gains and losses on the Company’s available-for-sale investments. Foreign Currency The functional currency of the Company’s foreign subsidiaries is the U.S. Dollar. Accordingly, all monetary assets and liabilities of the subsidiary are remeasured at the current exchange rate at the end of the period, nonmonetary assets and liabilities are remeasured at historical rates, and revenue and expenses are remeasured at average exchange rates during the period. There were net foreign currency transaction losses of $1.8 million, $1.1 million, and $0.8 million for the years ended December 31, 2023, 2022, and 2021 respectively. Net Income (Loss) Per Share Basic net income (loss) per share is calculated by dividing net income (loss) by the weighted-average number of shares of common stock outstanding for the period, without consideration of potential dilutive shares of common stock. Diluted net income (loss) per share attributable to the Company’s stockholders is calculated based on the weighted-average number of shares of its common stock and other dilutive securities outstanding. Where the Company was in a loss position for any periods presented, basic net loss per share was the same as diluted net loss per share since the effects of potentially dilutive securities are antidilutive. The Company uses the if-converted method of calculating diluted earnings per share. Under the “if-converted” method, diluted earnings per share will generally be calculated assuming that all the Notes (as defined below) were converted solely into shares of common stock at the beginning of the reporting period, unless the result would be anti-dilutive. Because the principal amount of the Notes upon conversion is required to be paid in cash, and only the excess is permitted to be settled in shares, the application of the if-converted method will produce a similar result as the treasury stock method prior to the adoption of ASU 2020-06, Debt-Debt with Conversion and Other Options (Subtopic 470-20) and Derivatives and Hedging-Contracts in Entity ’ s Own Equity (Subtopic 815-40)-Accounting For Convertible Instruments and Contracts in an Entity ’ s Own Equity (“ASU 2020-06”). The effect of the treasury stock method is that the shares issuable upon conversion of such Notes are not included in the calculation of diluted earnings per share except to the extent that the conversion value of such Notes exceeds their principal amount. Prior to conversion of the Company’s convertible debt, the Company will include, in the diluted net income per common share calculation, the effect of the additional shares that may be issued when the Company’s common stock price exceeds the conversion price using the if‐converted method. The Company’s convertible debt has no impact on diluted net income per common share unless the average price of the Company’s common stock exceeds the conversion price because the Company is required to settle the principal amount of the convertible debt in cash upon conversion. Income Taxes The Company uses the asset and liability method of accounting for income taxes. Under this method, deferred tax assets and liabilities are determined based on the differences between the financial reporting and the tax bases of assets and liabilities and are measured using the enacted tax rates and laws that will be in effect when the differences are expected to reverse. Deferred tax assets are evaluated for future realization and reduced by a valuation allowance to the extent the Company believes it is more likely than not that they will not be realized. The Company considers all available positive and negative evidence, including future reversals of existing taxable temporary reversals of existing taxable temporary differences, projected future taxable income, tax-planning strategies, carryback potential if permitted under the tax law, and results of recent operations. The Company also accounts for uncertain tax positions in accordance with ASC 740, Income Taxes – Accounting for Income Taxes ( “ ASC 740 ” ) , which requires the Company to adjust the financial statements to reflect only those tax positions that are more-likely-than-not to be sustained upon review by federal or state examiners. The Company may recognize a tax benefit only if it is more likely than not the tax position will be sustained on examination by the taxing authorities, based on the technical merits of the position. The tax benefits recognized in the financial statements from such positions are then measured based on the largest benefit that has a greater than 50% likelihood of being realized upon settlement. The Company’s policy is to recognize interest and penalties related to the underpayment of income taxes as a component of provision for income taxes. Segment Reporting Operating segments are defined as components of an entity for which separate financial information is available and that is regularly reviewed by the Chief Operating Decision Maker (“CODM”) in deciding how to allocate resources to an individual segment and in assessing performance. The Company’s CODM is its Chief Executive Officer. The Company has determined that it operates in one segment. The Company’s long-lived assets are held predominantly in the United States with the exception of the Company ’ s long lived assets in Costa Rica and Japan which collectively encompass approximately 32% and 15%, respectively, of its consolidated net property, plant, and equipment as of December 31, 2023 and 2022. See the section titled “Risk Factors” in Part I, Item 1A of this Annual Report on Form 10-K for a description of risk associated with the Company ’ s operations located outside of the United States. Internal-Use Software The Company has internal-use software consisting of cloud-based hosting arrangements with service contracts. The Company capitalizes certain costs incurred to implement such software within prepaid expenses and other current assets, or within other assets. Eligible costs of internal use software and implementation costs of certain hosting arrangements are capitalized. Once the software is ready for its intended use, the Company starts amortizing the capitalized implementation costs on a straight-line basis over the estimated service term or associated hosting arrangement, as applicable. Business combinations The Company applies the provisions of ASC 805, Business Combinations ( “ ASC 805 ” ) , in accounting of its acquisitions. ASC 805 requires recognition of assets acquired, liabilities assumed, and contingent consideration at their fair value on the acquisition date with subsequent changes recognized in earnings; requires acquisition-related expenses to be recognized separately from the business combination and expensed as incurred; requires in-process research and development to be capitalized at fair value as an indefinite-lived intangible asset until completion or abandonment; and requires that changes in accounting for deferred tax asset valuation allowances and acquired uncertain tax positions after the measurement period be recognized as a component of provision for taxes. When an integrated set of assets and activities does not meet the practical screen test and otherwise meets the definition of a “business” under ASC 805, the Company accounts for such acquisitions as business combinations. The purchase price of an acquisition is allocated to the tangible and identifiable intangible assets acquired and liabilities assumed based on their estimated fair values as of the acquisition date. The Company bases the estimated fair value of identifiable intangible assets acquired in an acquisition on independent third-party valuations that use information and assumptions provided by the Company ’ s management and considers inputs and assumptions that a market participant would use. Any excess purchase price over the estimated fair values of the assets acquired and liabilities assumed is recorded as goodwill. During the measurement period, which may be up to one year from the acquisition date, the Company may record adjustments to the provisional amounts of assets acquired and liabilities assumed with the corresponding offset to goodwill. Upon the conclusion of the measurement period or final determination of the values of assets acquired or liabilities assumed, whichever comes first, any subsequent adjustments would be recorded in earnings. In addition, uncertain tax positions and tax related valuation allowances assumed in a business combination are initially estimated as of the acquisition date and therefore are also provisional by nature. The Company reevaluates these items quarterly based upon facts and circumstances that existed as of the acquisition date with any adjustments to its preliminary estimates being recorded to goodwill if identified within the measurement period. Goodwill In accordance with ASC 350, Intangibles-Goodwill and Other ( “ ASC 350 ” ) , acquired goodwill is not amortized but is tested for impairment on an annual basis or whenever events or changes in circumstances indicate that the carrying amount of these assets may not be recoverable. The Company performs annual impairment reviews of its goodwill balance during the fourth fiscal quarter or more frequently if business factors indicate. In testing for impairment, the Company compares the fair value of its reporting unit to its carrying value including the goodwill of that unit. If the carrying value, including goodwill, exceeds the reporting unit’s fair value, the Company will recognize an impairment loss for the amount by which the carrying amount exceeds the reporting unit’s fair value. The loss recognized cannot exceed the total amount of goodwill allocated to that reporting unit. The Company did not incur any goodwill impairment losses during the year ended December 31, 2023. In-process research and development Intangible assets related to in-process research and development costs are considered indefinite-lived intangible assets until the completion or abandonment of the associated research and development efforts. If and when development is complete, the associated assets would be deemed finite-lived intangible assets and would then be amortized based on their respective estimated useful lives at that point in time. Prior to the completion or abandonment of the associated research and development efforts, the assets are not amortized but are tested for impairment on an annual basis and between annual tests if the Company becomes aware of any events occurring or changes in circumstances that would indicate a reduction in the fair value of the in-process research and development projects below their respective carrying amounts. During the fourth fiscal quarter and if business factors indicate more frequently, the Company performs an assessment of the qualitative factors affecting the fair value of its in-process research and development projects. If the fair value exceeds the carrying value, there is no impairment. Impairment losses on indefinite-lived intangible assets are recognized based solely on a comparison of the fair value of an asset to its carrying value, without consideration of any recoverability test. The Company did not incur any impairment losses during the year ended December 31, 2023. Intangible assets Amortizable intangible assets include customer relationships and developed technology acquired as part of business combinations. Customer relationships and developed technology acquired through business combinations subject to amortization are amortized using the straight-line method over their estimated useful lives ranging from five to 20 years. All intangible assets subject to amortization are reviewed for impairment during the fourth fiscal quarter or more frequently if business factors indicate in accordance with ASC 360, Property, Plant and Equipment ( “ ASC 360 ” ) . The Company did not incur any impairment losses during the year ended December 31, 2023. Contingent Consideration Liabilities Related to Business Combination At each reporting period, the Company evaluates the likelihood of any expected future payments and the associated discount rate to determine the fair value of the contingent consideration. The Company remeasures the fair value of contingent consideration liabilities each reporting period, based on new developments, and records any necessary adjustments as a component of total operating expenses within the consolidated statements of operations until either the contingent consideration obligation is satisfied through payment upon the achievement of, or the obligation no longer exists due to the failure to achieve, the specified milestones. Contingent consideration liabilities are recorded within other liabilities in the consolidated balance sheets. Convertible Debt The Company applies the provisions of ASU 2020-06 which simplify the accounting related to convertible debt instruments by removing major separation models required under current GAAP. Accordingly, the Company does not bifurcate the liability and equity components of the convertible debt on the co |
