Summary of Significant Accounting Policies | Note 2. Summary of Significant Accounting Policies There have been no significant changes in the Company’s significant accounting policies during the six months ended June 30, 2018, as compared with those disclosed in its Annual Report on Form 10-K for the year ended December 31, 2017 filed with the SEC on February 28, 2018, with the exception of the Company’s adoption of Accounting Standards Codification (ASC) 606, Revenue Recognition – Revenue from Contracts with Customers and its related amendments (ASC 606). See section below entitled “Revenue recognition” and Note 6, Revenue from Contracts with Customers for further discussion of the Company’s adoption of ASC 606 and related disclosures. Use of estimates The preparation of the financial statements in conformity with GAAP requires management to make estimates and assumptions that affect the reported amounts in the financial statements and accompanying notes. Actual results could differ materially from those estimates and assumptions. Management considers many factors in selecting appropriate financial accounting policies and controls and in developing the estimates and assumptions that are used in the preparation of these financial statements. Management must apply significant judgment in this process. In addition, other factors may affect estimates, including expected business and operational changes, sensitivity and volatility associated with the assumptions used in developing estimates, and whether historical trends are expected to be representative of future trends. The estimation process often may yield a range of potentially reasonable estimates of the ultimate future outcomes, and management must select an amount that falls within that range of reasonable estimates. The most significant estimates in the accompanying condensed consolidated financial statements relate to revenue recognition and stock‑based compensation expense. Although these estimates are based on the Company’s knowledge of current events and actions it may undertake in the future, this process may result in actual results differing materially from those estimated amounts used in the preparation of the financial statements. Foreign currency translation The accompanying condensed consolidated financial statements are presented in U.S. dollars. The Company considers the local currency to be the functional currency for its international subsidiaries. Accordingly, their assets and liabilities are translated into U.S. dollars using the exchange rate in effect on the balance sheet date. Revenues and expenses are translated at average exchange rates prevailing throughout the periods presented. As a result, currency translation adjustments arising from period to period are charged or credited to accumulated other comprehensive income (loss) in stockholders’ equity. For the three and six months ended June 30, 2018, the Company reported foreign currency translation gains of approximately $1.5 million and $1.0 million, respectively. For the three and six months ended June 30, 2017, the Company reported foreign currency translation losses of approximately $0.3 million and $0.7 million, respectively. Realized gains and losses resulting from foreign currency transactions are included in selling, general and administrative expense in the condensed consolidated statements of operations. For the three and six months ended June 30, 2018, the Company reported foreign currency transaction losses of approximately $0.2 million and $0.3 million, respectively. For each of the three and six month periods ended June 30, 2017, the Company reported foreign currency transaction gains of approximately $0.1 million. Unrealized gains and losses that arise from exchange rate fluctuations on transactions denominated in a currency other than the functional currency, primarily gains and losses on intercompany loans, are included in the condensed consolidated statements of operations as a component of other (expense) income, net. For the three and six months ended June 30, 2018, the Company reported net unrealized foreign currency transaction losses of $1.7 million and $1.2 million, respectively. For the three and six months ended June 30, 2017, the Company reported net unrealized foreign currency transaction gains of $0.3 million and $0.6 million, respectively. Cash, cash equivalents and short-term investments The Company invests its excess cash in marketable securities, including money market funds, money market securities, bank certificates of deposits, corporate bonds, corporate commercial paper, U.S. government bonds and U.S. government agency bonds. For financial reporting purposes, liquid investment instruments purchased with an original maturity of three months or less are considered to be cash equivalents. Cash and cash equivalents are recorded at face value or cost, which approximates fair market value. The Company maintains cash balances in excess of amounts insured by the Federal Deposit Insurance Commission. Investments are stated at fair value as determined by quoted market prices. Investments are considered available-for-sale and, accordingly, unrealized gains and losses are included in accumulated other comprehensive income (loss) within stockholders’ equity. The Company’s entire investment portfolio is considered to be available for use in current operations and, accordingly, all such investments are stated at fair value using quoted market prices and classified as current assets, although the stated maturity of individual investments may be one year or more beyond the balance sheet date. The Company did not have any trading securities or restricted investments at June 30, 2018 or December 31, 2017. Realized gains and losses and declines in value, if any, judged to be other-than-temporary on available-for-sale securities are reported in other (expense) income, net. When securities are sold, any associated unrealized gain or loss previously reported as a separate component of stockholders’ equity is reclassified out of stockholders’ equity and recorded in the statements of operations in the period sold using the specific identification method. Accrued interest and dividends are included in other (expense) income, net. The Company periodically reviews its available-for-sale securities for other-than-temporary declines in fair value below the cost basis, and whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. Fair value of financial instruments The carrying amounts of cash equivalents, accounts receivable, accounts payable, and accrued liabilities are considered to be representative of their respective fair values because of the short-term nature of those instruments. The valuation of assets and liabilities is subject to fair value measurements using a three-tiered approach and fair value measurements are classified and disclosed by the Company in one of the following three categories: Level 1: Unadjusted quoted prices in active markets that are accessible at the measurement date for identical, unrestricted assets or liabilities; Level 2: Quoted prices for similar assets and liabilities in active markets, quoted prices in markets that are not active, or inputs which are observable, either directly or indirectly, for substantially the full term of the asset or liability; and Level 3: Prices or valuation techniques that require inputs that are both significant to the fair value measurement and unobservable (i.e., supported by little or no market activity). Revenue recognition Effective January 1, 2018, the Company adopted Accounting Standards Codification (ASC) 606 , Revenue from Contracts with Customers . The Company adopted the standard by applying the modified retrospective method to contracts that were not complete as of the date of initial application. The Company’s accounting for revenue under ASC 606 is materially consistent with the accounting for revenue under ASC 605 and therefore the cumulative effect of adoption was immaterial. The reported results for the three and six months ended June 30, 2018 reflect the application of ASC 606 guidance while the reported results for periods prior to January 1, 2018 were prepared under the guidance of ASC 605. The Company accounts for revenue in accordance with ASC 606 and applies 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 Company satisfies a performance obligation. The Company only applies the five-step model to contracts when it is probable that the entity will collect the consideration it is entitled to in exchange for the goods it transfers to the customer. At contract inception, once the contract is determined to be within the scope of ASC 606, the Company assesses the goods promised within each contract and determines those that are performance obligations, and assesses whether each promised good or service is distinct. The Company then recognizes as revenue the amount of the transaction price that is allocated to the respective performance obligation when (or as) the performance obligation is satisfied. As part of the Company's adoption of ASC 606, the Company elected to use the following practical expedients: (i) to exclude disclosures of transaction prices allocated to remaining performance obligations when the Company expects to recognize such revenue within one year; (ii) to expense costs as incurred for costs to obtain a contract when the amortization period would have been one year or less, which mainly includes the Company's internal sales force compensation program; (iii) to account for shipping and handling costs as fulfillment costs (i.e., as an expense) rather than promised service (i.e., a revenue element); and (iv) to exclude from revenue the taxes collected from customers relating to product sales which are remitted to governmental authorities. The Company derives its revenue from sales of its products in the United States and internationally. Customers are primarily comprised of ambulatory surgery centers and hospitals, with distributors being used in certain international locations where the Company does not have a direct commercial presence. The Company concluded that one performance obligation exists for the majority of its contracts with customers which is to deliver products in accordance with the Company’s normal delivery times. Revenue is recognized when this performance obligation is satisfied at a point in time when the Company considers control of a product to have transferred to the customer. Revenue recognized reflects the consideration to which the Company expects to be entitled in exchange for those products or services. The Company has determined the transaction price to be the invoice price, net of adjustments, which includes estimates of variable consideration for product returns. The Company offers volume-based rebate agreements to certain customers and, in these instances, the Company provides a rebate (in the form of a credit memo) at the contract’s conclusion, if earned by the customer. In such cases, the transaction price is allocated between the Company’s delivery of product and the issuance of a rebate at the contract’s conclusion for the customer to utilize on prospective purchases. The performance obligation to issue a customer’s rebate, if earned, is transferred over time and the Company’s method of measuring progress is the output method, whereby, the progress is measured by the estimated rebate earned to date over the total rebate estimated to be earned over the contract period. The provision for volume-based rebates is estimated based on customers' contracted rebate programs and the customers’ projected sales levels. The Company periodically monitors its customer rebate programs to ensure the rebate allowance is fairly stated. The Company’s rebate allowance is included in accrued liabilities in the condensed consolidated balance sheets and estimated rebates accrued were not material during the periods presented. Customers are not granted specific rights of return; however, the Company may permit returns of product from customers if such product is returned in a timely manner and in good condition. The Company provides a warranty on its products for one year from the date of shipment, and any product found to be defective or out of specification will be replaced at no charge during the warranty period. Estimated allowances for sales returns and warranty replacements are recorded at the time of sale of the product and are estimated based upon the historical patterns of product returns matched against sales, and an evaluation of specific factors that may increase the risk of product returns. Product returns and warranty replacements to date have been consistent with amounts reserved or accrued and have not been significant. If actual results in the future vary from the Company’s estimates, the Company will adjust these estimates which would affect net product revenue and earnings in the period such variances become known. Research and development expenses Major components of research and development expense include personnel costs, preclinical studies, clinical trials and related clinical product manufacturing, materials and supplies, and fees paid to consultants. Research and development costs are expensed as goods are received or services are rendered. Costs to acquire technologies to be used in research and development that have not reached technological feasibility and have no alternative future use are also expensed as incurred. At each financial reporting date, the Company accrues the estimated unpaid costs of clinical study activities performed during a period by third party clinical sites with whom the Company has agreements that provide for fees based upon the quantities of subjects enrolled and clinical evaluation visits that occur over the life of the study. The cost estimates are determined based upon a review of the agreements and data collected by internal and external clinical personnel as to the status of enrollment and subject visits, and are based upon the facts and circumstances known to the Company at each financial reporting date. If the actual performance of activities varies from the assumptions used in the cost estimates, the accruals are adjusted accordingly. There have been no material adjustments to the Company’s prior period accrued estimates for clinical trial activities through June 30, 2018. Stock‑based compensation The Company recognizes compensation expense for all stock-based awards granted to employees and nonemployees, including members of its board of directors. The fair value of stock option awards is estimated at the grant date using the Black-Scholes option pricing model, and the portion that is ultimately expected to vest is recognized as compensation cost over the requisite service period using the straight-line method. The determination of the fair value-based measurement of stock options on the date of grant using an option pricing model is affected by the determination of the fair value of the underlying stock as well as assumptions regarding a number of highly complex and subjective variables. These variables include, but are not limited to, the Company’s stock price volatility over the expected term of the grants, and actual and projected employee stock option exercise behaviors. In the future, as additional empirical evidence regarding these estimates becomes available, the Company may change or refine its approach of deriving them, and these changes could impact the fair value-based measurement of stock options granted in the future. Changes in the fair value-based measurement of stock awards could materially impact the Company’s operating results. The fair values of stock option awards made to nonemployees are re-measured at each reporting period using the Black-Scholes option pricing model. Compensation expense for these stock option awards is determined by applying the re-measured fair values to the shares that have vested during a period. The fair value of restricted stock unit (RSU) awards made to employees and nonemployees is equal to the closing market price of the Company’s common stock on the grant date. Net loss per share Basic net loss per share is calculated by dividing the net loss by the weighted average number of common shares that were outstanding for the period, without consideration for common stock equivalents. For periods when the Company realizes a net loss, no common stock equivalents are included in the calculation of weighted average number of dilutive common stock equivalents as the effect of applying the treasury stock method is considered anti-dilutive. For periods when the Company realizes net income, diluted net income per share is calculated by dividing the net income by the weighted average number of common shares plus the sum of the weighted average number of dilutive common stock equivalents outstanding for the period determined using the treasury stock method. Common stock equivalents are comprised of stock options and RSUs outstanding under the Company’s stock option plans and shares issuable under the Company’s Employee Stock Purchase Plan (ESPP). The Company’s computation of net loss per share is as follows (in thousands, except per share amounts): Three Months Ended Six Months Ended June 30, June 30, 2018 2017 2018 2017 Numerator: Net loss – basic and diluted $ (5,398) $ (3,301) $ (8,109) $ (2,423) Denominator: Weighted average number of common shares outstanding - basic 34,942 34,322 34,778 34,234 Weighted average number of common shares outstanding - diluted 34,942 34,322 34,778 34,234 Basic net loss per share $ (0.15) $ (0.10) $ (0.23) $ (0.07) Diluted net loss per share $ (0.15) $ (0.10) $ (0.23) $ (0.07) Potentially dilutive securities not included in the calculation of diluted net loss per share because to do so would be anti-dilutive were as follows (in thousands): Three Months Ended Six Months Ended June 30, June 30, 2018 2017 2018 2017 Stock options outstanding 5,819 5,632 5,937 5,700 Unvested restricted stock units 141 105 333 105 ESPP 31 19 27 19 5,991 5,756 6,297 5,824 Recently adopted accounting pronouncements In November 2016, the Financial Accounting Standards Board (FASB) issued Accounting Standards Update (ASU) No. 2016-18, Statement of Cash Flows (Topic 230): Restricted Cash (ASC 2016-18), which enhances and clarifies the guidance on the classification and presentation of restricted cash in the statement of cash flows. ASU 2016-18 was effective for the Company beginning on January 1, 2018 and was required to be adopted retrospectively. Historically, the Company’s restricted cash balance has not been significant and the adoption of the guidance did not have a material impact on its condensed consolidated financial statements. In January 2017, the FASB issued ASU No. 2017-01, Business Combinations (Topic 805): Clarifying the Definition of a Business (ASU 2017-01). The amendments are intended to help companies evaluate whether transactions should be accounted for as acquisitions (or disposals) of assets or businesses. When substantially all of the fair value of gross assets acquired is concentrated in a single asset (or a group of similar assets), the assets acquired would not represent a business. This introduces an initial required screening that, if met, eliminates the need for further assessment. To be considered a business, an acquisition would have to include an input and a substantive process that together significantly contribute to the ability to create outputs. To be a business without outputs, there will need to be an organized workforce. The ASU also narrows the definition of the term “outputs” to be consistent with how it is described in ASC 606, Revenue Recognition - Revenue from Contracts with Customers . The amendments were effective for annual periods beginning after December 15, 2017, including interim periods within those periods with early adoption permitted. The Company adopted the guidance effective January 1, 2018 and the guidance did not have a material impact on its condensed consolidated financial statements; however, any prospective impact to the Company’s condensed consolidated financial statements will depend on the terms specified in any future transactions subject to the guidance in ASU 2017-01. In May 2017, the FASB issued ASU No. 2017-09, Compensation - Stock Compensation - Scope of Modification Accounting (ASU 2017-09). The standard provides clarification on when modification accounting should be used for changes to the terms or conditions of a share-based payment award. This standard does not change the accounting for modifications but clarifies that modification accounting guidance should only be applied if there is a change to the value, vesting conditions, or award classification and would not be required if the changes are considered non-substantive. The standard was effective for annual periods beginning after December 15, 2017, and interim periods within those annual periods and early adoption was permitted. The Company adopted the guidance on a prospective basis effective January 1, 2018 and the adoption of ASU 2017-09 did not have a material impact on its condensed consolidated financial statements; however, any future impact to share-based compensation expense will depend on the terms specified in any new changes to share-based payment awards subsequent to the adoption. Recently issued accounting pronouncements not yet adopted In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842) , which amends the existing accounting standards for leases. In September 2017, the FASB issued ASU No. 2017-13 which provides additional clarification and implementation guidance on the previously issued ASU No. 2016-02. Under the new guidance, a lessee will be required to recognize a lease liability and right-of-use asset for all leases with terms in excess of twelve months. The new guidance also modifies the classification criteria and accounting for sales-type and direct financing leases, and requires additional disclosures to enable users of financial statements to understand the amount, timing, and uncertainty of cash flows arising from leases. Consistent with current guidance, a lessee’s recognition, measurement, and presentation of expenses and cash flows arising from a lease will continue to depend primarily on its classification. The accounting standard is effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years, and must be applied using a modified retrospective approach. Early adoption is permitted. While the Company is continuing to assess all potential impacts of the standard, it expects that most of its lease commitments will be subject to the updated standard and recognized as lease liabilities and right-of-use assets upon adoption. In February 2018, the FASB issued ASU No. 2018-02, Income Statement – Reporting Comprehensive Income (Topic 220): Reclassification of Certain Tax Effects from Accumulated Other Comprehensive Income that gives entities the option to reclassify to retained earnings tax effects related to items that have been stranded in accumulated other comprehensive income as a result of the Tax Cuts and Jobs Act (the Act). A company that elects to reclassify these amounts must reclassify stranded tax effects related to the Act’s change in U.S. federal tax rate for all items accounted for in other comprehensive income. Companies can also elect to reclassify other stranded effects that relate to the Act but do not directly relate to the change in the federal rate. Companies can choose whether to apply the amendments retrospectively to each period in which the effect of the Act is recognized or to apply the amendments in the period of adoption. The guidance is effective for all companies for fiscal years beginning after December 15, 2018, and interim periods within those fiscal years. Early adoption is permitted. Entities can choose whether to apply the amendments retrospectively to each period in which the effect of the Act is recognized or to apply the amendments in the period of adoption, and the Company is assessing the potential impacts of the standard. In June 2018, the FASB issued ASU No. 2018-07, Improvements to Nonemployee Share-Based Payment Accounting (ASU 2018-07). ASU 2018-07 simplifies the accounting for share-based payments to nonemployees by aligning it with the accounting for share-based payments to employees, with certain exceptions. Consistent with the accounting requirement for employee share-based payment awards, nonemployee share-based payment awards are measured at grant-date fair value of the equity instruments that an entity is obligated to issue when the good has been delivered, or the service has been rendered, and any other conditions necessary to earn the right to benefit from the instruments have been satisfied. The accounting standard is effective for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years and the Company is assessing the potential impacts of the standard. |