Summary of Significant Accounting Policies | 3. Basis of Presentation The accompanying unaudited interim condensed consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States of America (“U.S. GAAP”). In the Company’s opinion, the accompanying unaudited interim condensed consolidated financial statements include all adjustments, consisting of normal recurring adjustments, which are necessary to present fairly its financial position, results of operations, and cash flows. The consolidated balance sheet at December 31, 2016, has been derived from audited financial statements as of that date. The interim condensed consolidated results of operations are not necessarily indicative of the results that may occur for the full fiscal year. Certain information and footnote disclosure normally included in financial statements prepared in accordance with U.S. GAAP have been omitted pursuant to instructions, rules, and regulations prescribed by the U.S. Securities and Exchange Commission (“SEC”). The Company believes that the disclosures provided herein are adequate to make the information presented not misleading when these unaudited interim condensed consolidated financial statements are read in conjunction with the audited financial statements and notes previously included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2016. Use of Estimates The preparation of consolidated 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 reported amounts of revenues and expenses during the reporting period. In the accompanying consolidated financial statements, estimates are used for, but not limited to, stock-based compensation, recoverability of long-lived assets, deferred taxes and valuation allowances, depreciable lives of property and equipment, and estimated accruals for preclinical study costs, which are accrued based on estimates of work performed under contracts. Actual results could differ from those estimates; however management does not believe that such differences would be material. Segment Information Operating segments are defined as components of an enterprise about which separate discrete financial information is available for evaluation by the chief operating decision-maker, or decision-making group, in deciding how to allocate resources and in assessing performance. The Company views its operations and manages its business in one segment, glucose monitoring systems. Comprehensive Income (Loss) Comprehensive income (loss) comprises net income (loss) and other changes in equity that are excluded from net income (loss). For the three months ended March 31, 2017 and 2016, the Company’s net loss equaled its comprehensive loss and, accordingly, no additional disclosure is presented. Inventory Inventory consist principally of finished goods and is valued at the lower of cost to purchase or the net realizable value of such inventory. Cost is determined using the standard cost method that approximates first in, first out. Market is determined by the lower of replacement cost or net realizable value. The Company periodically reviews inventory to determine if a write down is necessary for inventory that has become obsolete, inventory that has a cost basis less than net realizable value, and inventory in excess of future demand taking into consideration the product shelf life. Marketable Securities Marketable securities consist of debt securities in government-sponsored entities, corporate debt securities, U.S. Treasury securities and commercial paper. The Company’s investments are classified as available for sale. Such securities are carried at estimated fair value, with any unrealized holding gains or losses reported, net of any tax effects reported, as accumulated other comprehensive income. Realized gains and losses, and declines in value judged to be other-than-temporary, if any, are included in consolidated results of operations. A decline in the market value of any available for sale security below cost that is deemed to be other-than-temporary results in a reduction in fair value, which is charged to earnings in that period, and a new cost basis for the security is established. Dividend and interest income is recognized when earned. The cost of securities sold is calculated using the specific identification method. The Company classifies all available-for-sale marketable securities with maturities greater than one year from the balance sheet date as non-current assets. Revenue Recognition Revenue is generated from sales of sensor kits, transmitter kits, and related supplies under agreements for third-party distributors that resell the product to customers. The Company is paid for its sales directly by third-party distributors, regardless of whether or not the distributors resell the products to their customers. The Company recognizes product sales revenue when all of the following criteria are met: persuasive evidence of an arrangement exists; delivery has occurred; the price is fixed or determinable; and collectability is reasonably assured. The Company offers no rights of return and has no significant post-delivery obligations and therefore, the above criteria are generally met as products are shipped to, or received by, third-party distributors. Accounts Receivable The Company grants credit to various customers in the normal course of business. Accounts receivable consist of amounts due from distributors. The Company records an allowance for doubtful accounts at the time potential collection risk is identified. Uncollectible accounts are written off against the allowance after appropriate collection efforts have been exhausted and when it is deemed that a balance is uncollectible. Warranty Reserve The Company generally provides a warranty on Eversense to end user customers and may replace Eversense components that do not function in accordance with the product specifications. Estimated warranty costs associated with a product are recorded at the time of shipment. The Company estimates future warranty costs by analyzing historical warranty experience for the timing and amount of returned product, and the Company evaluates the reserve quarterly and makes adjustments when appropriate. Property and Equipment Property and equipment are stated at historical cost and depreciated on a straight-line basis over the estimated useful lives, generally five years. Equipment under capital leases is depreciated on a straight-line basis over the lesser of its estimated useful life or the lease term. Leasehold improvements are depreciated over the shorter of the remaining lease term or useful lives of the assets. Upon disposition of the assets, the costs and related accumulated depreciation are removed from the accounts and any resulting gain or loss is included in the results of operations. Repairs and maintenance costs are included as expense in the accompanying statement of operations and comprehensive income (loss). Management reviews property and equipment for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. Recoverability of the long-lived asset is measured by a comparison of the carrying amount of the asset to future undiscounted net cash flows expected to be generated by the asset. If the undiscounted cash flows are less than the carrying amount, the impairment to be recognized is measured by the amount by which the carrying amount of the assets exceeds the estimated fair value of the assets. Management did not identify any indicators of impairment through March 31, 2017. Research and Development Costs Research and development costs are expensed as incurred. Research and development expenses include costs related to employee compensation, preclinical studies and clinical trials, supplies, outsource testing, consulting and depreciation and other facilities‑related expenses. Stock‑Based Compensation The Company recognizes the cost of employee services received in exchange for awards of equity instruments, such as stock options, based on the fair value of those awards at the date of grant. The estimated fair value of stock options on the date of grant is amortized on a straight‑line basis over the requisite service period for each separately vesting portion of the award for those awards with service conditions only. For awards that also contain performance conditions, expense is recognized beginning at the time the performance condition is considered probable of being met over the remaining vesting period. The Company uses the Black‑Scholes option pricing model to determine the fair value of stock‑option awards. Valuation of stock awards requires management to make assumptions and to apply judgment to determine the fair value of the awards. These assumptions and judgments include estimating the fair value of the Company’s common stock, future volatility of the Company’s stock price, dividend yields, future employee turnover rates, and future employee stock option exercise behaviors. Changes in these assumptions can affect the fair value estimate. Under Accounting Standards Codification (“ASC”) 718, the cumulative amount of compensation cost recognized for instruments classified as equity that ordinarily would result in a future tax deduction under existing tax law shall be considered to be a deductible difference in applying ASC 740, Income Taxes . The deductible temporary difference is based on the compensation cost recognized for financial reporting purposes; however, these provisions currently do not impact the Company, as all the deferred tax assets have a full valuation allowance. Since the Company had net operating loss (“NOL”) carryforwards as of March 31, 2017, no excess tax benefits for the tax deductions related to stock-based awards were recognized in the statement of operations and comprehensive income (loss). Fair Value of Financial Instruments The carrying amounts of cash and cash equivalents, accounts receivable, accounts payable, and accrued expenses approximate fair value because of their short maturities. The carrying amount of the Company’s term notes payable approximate fair value as they were issued in the current year. The fair values of the Company’s marketable investments are reported in Note 11 —Fair Value Measurements. Income Taxes The Company uses the asset and liability method of accounting for income taxes. Deferred tax assets and liabilities are determined based on differences between the financial reporting and tax basis of assets and liabilities and are measured using the enacted tax rates and laws that are in effect when the differences are expected to reverse. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in the period that such tax rate changes are enacted. The measurement of a deferred tax asset is reduced, if necessary, by a valuation allowance if it is more likely than not that some portion or all of the deferred tax asset will not be realized. Management uses a recognition threshold and a measurement attribute for the financial statement recognition and measurement of tax positions taken or expected to be taken in a tax return, as well as guidance on derecognition, classification, interest and penalties and financial statement reporting disclosures. For those benefits to be recognized, a tax position must be more-likely-than-not to be sustained upon examination by taxing authorities. In the ordinary course of business, transactions occur for which the ultimate outcome may be uncertain. Management does not expect the outcome related to accrued uncertain tax provisions to have a material adverse effect on the Company’s financial position, results of operations or cash flows. The Company recognizes interest and penalties accrued on any unrecognized tax exposures as a component of income tax expense. The Company did not have any amounts accrued relating to interest and penalties as of March 31, 2017 and December 31, 2016. The Company is subject to taxation in various jurisdictions in the United States and remains subject to examination by taxing jurisdictions for the year 1998 and all subsequent periods due to the availability of net operating loss carryforwards. In addition, all of the net operating losses and research and development credit carryforwards that may be used in future years are still subject to adjustment. Net Loss per Share Basic net loss per share is computed by dividing net loss by the weighted average number of shares of common stock outstanding during the period. For periods of net loss, diluted net loss per share is calculated similarly to basic loss per share because the impact of all potential dilutive common shares is anti‑dilutive. The total number of anti‑dilutive shares, consisting of common stock options and stock purchase warrants exercisable for common stock, which have been excluded from the computation of diluted loss per share, was 13,605,558 and 9,247,130 common stock options and 4,570,902 and 5,010,595 stock purchase warrants for three months ended March 31, 2017 and 2016, respectively. For periods of net income, and when the effects are not anti-dilutive, diluted earnings per share is computed by dividing net income available to common stockholders by the weighted-average number of shares outstanding plus the impact of all potential dilutive common shares, consisting primarily of common stock options and stock purchase warrants using the treasury stock method. Recent Accounting Pronouncements In May 2014, the Financial Accounting Standards Board (“FASB”) issued guidance for revenue recognition for contracts, superseding the previous revenue recognition requirements, along with most existing industry-specific guidance. The guidance requires an entity to review contracts in five steps: 1) identify the contract, 2) identify performance obligations, 3) determine the transaction price, 4) allocate the transaction price, and 5) recognize revenue. The new standard will result in enhanced disclosures regarding the nature, amount, timing, and uncertainty of revenue arising from contracts with customers. In August 2015, the FASB issued guidance approving a one-year deferral, making the standard effective for reporting periods beginning after December 15, 2017, with early adoption permitted only for reporting periods beginning after December 15, 2016. In March 2016, the FASB issued guidance to clarify the implementation guidance on principal versus agent considerations for reporting revenue gross rather than net, with the same deferred effective date. In April 2016, the FASB issued guidance to clarify the implementation guidance on identifying performance obligations and the accounting for licenses of intellectual property, with the same deferred effective date. In May 2016, the FASB issued guidance rescinding SEC paragraphs related to revenue recognition, pursuant to two SEC Staff Announcements at the March 3, 2016 Emerging Issues Task Force meeting. In May 2016, the FASB also issued guidance to clarify the implementation guidance on assessing collectability, presentation of sales tax, noncash consideration, and contracts and contract modifications at transition, with the same effective date. The Company does not intend to adopt the guidance early. The Company is in the process of reviewing its revenue accounting policy and implementing changes to its business processes and controls in response to the new standard. During the second half of 2017, the Company will finalize its revenue related documentation. Based on its evaluation, the Company anticipates selecting its method of adopting the new standard in the second quarter of 2017, which the Company will begin applying in the first quarter of 2018. In April 2015, the FASB issued accounting guidance related to Internal‑Use Software specifically for the Customer’s Accounting for Fees Paid in a Cloud Computing Arrangement. The amendments in this update provide guidance to customers about whether a cloud computing arrangement includes a software license. If a cloud computing arrangement includes a software license, then the customer should account for the software license element of the arrangement consistent with the acquisition of other software licenses. If a cloud computing arrangement does not include a software license, the customer should account for the arrangement as a service contract. The standard is effective for reporting periods beginning after December 15, 2015. An entity can elect to adopt the amendments either 1) prospectively for all arrangements entered into or materially modified after the effective date or 2) retrospectively. The Company decided to adopt the standards prospectively and will be accounting for the new cloud arrangements in accordance with the new standards. The adoption of this guidance did not have a material impact on the financial statements. In February 2016, the FASB issued guidance for accounting for leases. The guidance requires lessees to recognize assets and liabilities related to long-term leases on the balance sheet and expands disclosure requirements regarding leasing arrangements. The guidance is effective for reporting periods beginning after December 15, 2018 and early adoption is permitted. The guidance must be adopted on a modified retrospective basis and provides for certain practical expedients. The Company currently expects that the adoption of this guidance likely will change the way the Company accounts for its operating leases and likely will result in recording the future benefits of those leases and the related minimum lease payments on its balance sheet. The Company has not yet begun to evaluate the specific impacts of this guidance nor has it determined the manner in which it will adopt this guidance. In March 2016, the FASB issued guidance simplifying the accounting for and financial statement disclosure of stock-based compensation awards. The Company early adopted this guidance as of January 1, 2016. From January 1, 2016 onward, in accordance with the new guidance, no excess tax benefits or tax deficiencies will be recognized in additional paid-in capital. The Company will account for forfeitures as they occur, rather than using an estimated forfeiture rate. The Company estimates that this change in accounting will not result in material adjustment to retained earnings as of January 1, 2017. The Company will also present the impact of classifying excess tax benefits as an operating activity in the statement of cash flows on a prospective basis and prior periods will not be adjusted. The adoption of the remaining amendments is not expected to have a material impact on the Company’s consolidated financial statements. In June 2016, the FASB issued guidance with respect to measuring credit losses on financial instruments, including trade receivables. The guidance eliminates the probable initial recognition threshold that was previously required prior to recognizing a credit loss on financial instruments. The credit loss estimate can now reflect an entity's current estimate of all future expected credit losses. Under the previous guidance, an entity only considered past events and current conditions. The guidance is effective for fiscal years beginning after December 15, 2019, including interim periods within those fiscal years. Early adoption is permitted for fiscal years beginning after December 15, 2018, including interim periods within those fiscal years. The Company currently expects that the adoption of this guidance likely will change the way the Company assesses the collectibility of its receivables and recoverability of other financial instruments. The Company has not yet begun to evaluate the specific impacts of this guidance nor has it determined the manner in which it will adopt this guidance. In August 2016, the FASB issued guidance on the classification of certain cash receipts and cash payments in the statement of cash flows, including those related to debt prepayment or debt extinguishment costs, contingent consideration payments made after a business combination, proceeds from the settlement of insurance claims, proceeds from the settlement of corporate-owned life insurance, and distributions received from equity method investees. The guidance is effective for public business entities for fiscal years beginning after December 15, 2017, and for interim periods within those fiscal years. Early adoption is permitted, including adoption in an interim period. If an entity adopts the guidance in an interim period, any adjustments should be reflected as of the beginning of the fiscal year that includes that interim period. The guidance must be adopted on a retrospective basis and must be applied to all periods presented, but may be applied prospectively if retrospective application would be impracticable. The Company is currently evaluating the impact, if any, that the adoption of this guidance will have on its consolidated statement of cash flows. In November 2016, the FASB issued guidance to reduce diversity in practice that exists in the classification and presentation of changes in restricted cash on the statement of cash flows. The revised guidance requires that amounts generally described as restricted cash and restricted cash equivalents be included in with cash and cash equivalents when reconciling the beginning of period and end of period total amounts shown on the statement of cash flows. The guidance is effective for the fiscal years beginning after December 15, 2017, including interim periods within those fiscal years. Early adoption is permitted, including adoption in an interim period. If an entity adopts the guidance in an interim period, any adjustments should be reflected as of the beginning of the fiscal year that includes that interim period. The guidance must be adopted on a retrospective basis. The Company adopted this guidance as of January 1, 2017, on a retrospective basis, and all periods will be presented under this guidance. The adoption of this new guidance had no impact on the Company’s consolidated financial statements. The Company has evaluated all other issued unadopted Accounting Standards Updates and believes the adoption of these standards will not have a material impact on its consolidated statements of earnings, balance sheets, or cash flows. |