Entellus Medical (ENTL) 10-Q 5 May 17 2017 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2017	Apr. 27, 2017
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2017
Document Fiscal Year Focus	2,017
Document Fiscal Period Focus	Q1
Trading Symbol	ENTL
Entity Registrant Name	ENTELLUS MEDICAL INC
Entity Central Index Key	1,374,128
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding		21,916,451

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
CURRENT ASSETS
Cash and cash equivalents	$ 65,189	$ 21,417
Short-term investments	3,003	10,845
Accrued interest income	58	75
Accounts receivable, net of allowance for doubtful accounts and sales returns of $329 and $308, respectively	13,784	13,556
Inventories	7,324	7,226
Prepaid expenses and other current assets	1,852	1,787
Total current assets	91,210	54,906
Property and equipment, net	6,571	6,487
Intangible assets, net	9,662	9,840
Goodwill	477	477
Other non-current assets	235	379
Total assets	108,155	72,089
CURRENT LIABILITIES
Accounts payable	2,561	2,796
Accrued expenses	9,379	13,005
Revolving credit facility	8,000
Current portion of long-term debt		9,118
Total current liabilities	19,940	24,919
LONG-TERM LIABILITIES
Long-term debt, less current portion, net of debt issuance costs of $346 and $116, respectively	13,154	10,766
Other non-current liabilities	116	959
Total liabilities	33,210	36,644
COMMITMENTS AND CONTINGENCIES (See Note L)
STOCKHOLDERS' EQUITY (see Note H)
Preferred stock, $0.001 par value per share: Authorized shares: 10,000 at March 31, 2017 and December 31, 2016 Issued and outstanding shares: none
Common stock, $0.001 par value per share: Authorized shares: 200,000 at March 31, 2017 and December 31, 2016; Issued and outstanding shares: 21,916 and 18,908 at March 31, 2017 and December 31, 2016, respectively	22	19
Additional paid-in capital	234,193	186,370
Accumulated other comprehensive loss	(144)	(156)
Accumulated deficit	(159,126)	(150,788)
Total stockholders' equity	74,945	35,445
Total liabilities and stockholders' equity	$ 108,155	$ 72,089

Condensed Consolidated Balance3

Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Statement Of Financial Position [Abstract]
Allowance for doubtful accounts and sales returns	$ 329	$ 308
Debt issuance costs	$ 346	$ 116
Preferred stock, par value	$ 0.001	$ 0.001
Preferred stock, shares authorized	10,000,000	10,000,000
Preferred stock, shares Issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$ 0.001	$ 0.001
Common stock, shares authorized	200,000,000	200,000,000
Common stock, shares issued	21,916,000	18,908,000
Common stock, shares outstanding	21,916,000	18,908,000

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations and Comprehensive Loss - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Income Statement [Abstract]
Revenue	$ 19,106	$ 16,902
Cost of goods sold	4,896	4,000
Gross profit	14,210	12,902
Operating expenses
Selling and marketing	15,274	13,407
Research and development	2,103	1,912
General and administrative	4,664	3,949
Total operating expenses	22,041	19,268
Loss from operations	(7,831)	(6,366)
Other income (expense)
Interest income	62	70
Interest expense	(565)	(562)
Other non-operating expense	(1)	(14)
Loss before income tax expense	(8,335)	(6,872)
Income tax expense	(3)
Net loss	(8,338)	(6,872)
Other comprehensive loss
Unrealized gain on short-term investments, net of tax	2	69
Foreign currency translation loss	(14)	(11)
Comprehensive loss	$ (8,350)	$ (6,814)
Net loss per share, basic and diluted	$ (0.40)	$ (0.37)
Weighted average common shares used to compute net loss per share, basic and diluted	20,876	18,801

Condensed Consolidated Stateme5

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Cash flows from operating activities:
Net loss	$ (8,338)	$ (6,872)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	716	349
Amortization of debt issuance costs	15	15
Amortization of premium on investments	3	79
Accretion of final payment fee on long-term debt	77	77
Deferred tax expense	3
Deferred rent	(4)	3
Stock-based compensation	1,814	1,205
Changes in operating assets and liabilities:
Accrued interest income	17	135
Accounts receivables, net	(205)	164
Inventories	(98)	38
Prepaid expenses and other current assets	(64)	(10)
Other non-current assets	281	(71)
Accounts payable	(236)	396
Accrued expenses	(3,649)	115
Net cash used in operating activities	(9,668)	(4,377)
Cash flows from investing activities:
Purchase of property and equipment	(622)	(618)
Purchase of investments		(21,784)
Proceeds from maturities of short-term investments	7,837	21,950
Net cash provided by (used in) investing activities	7,215	(452)
Cash flows from financing activities:
Proceeds from revolving credit facility	8,000
Proceeds from long-term debt	13,500
Payment of term debt	(20,000)
Payment of debt fees	(1,206)
Payment of debt issuance costs	(95)
Proceeds from stock options exercised	669	47
Shares repurchased for payment of taxes on stock awards	(18)
Proceeds from public offering, net of issuance costs	45,361
Net cash provided by financing activities	46,211	47
Net increase (decrease) in cash and cash equivalents	43,758	(4,782)
Effect of exchange rate changes on cash and cash equivalents	14
Cash and cash equivalents - beginning of period	21,417	28,548
Cash and cash equivalents - end of period	65,189	23,766
Supplemental cash flow information:
Cash paid for interest	$ 630	$ 470

Organization

Organization	3 Months Ended
	Mar. 31, 2017
Accounting Policies [Abstract]
Organization	NOTE A. ORGANIZATION Nature of Business Entellus Medical, Inc. (the “Company”) was incorporated in Minnesota in April 2006 and was reincorporated in Delaware in August 2006. The Company is focused on delivering superior patient and physician experiences through products designed for the minimally invasive treatment of chronic and recurrent sinusitis patients. The Company’s platform of products provides effective and easy-to-use solutions designed to simplify everything from diagnosis and patient selection, to complex case revisions and post-operative care. The Company’s three core product lines, XprESS Multi-Sinus Dilation Systems, MiniFESS™ Surgical Instruments, and FocESS™ Imaging & Navigation, are designed to enable ear, nose and throat (“ENT”) physicians to conveniently and comfortably perform a broad range of procedures in the ENT physician office and simplify operating room-based treatment. The Company currently sells product through its direct sales force in the United States and United Kingdom and in a limited number of additional countries through international distributors. The Company operates in one reporting segment.

Summary of Significant Accounti

Summary of Significant Accounting Policies	3 Months Ended
	Mar. 31, 2017
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	NOTE B. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES Basis of Preparation The financial statements have been prepared in accordance with U.S. generally accepted accounting principles (“U.S. GAAP”) and pursuant to the rules and regulations of the United States Securities and Exchange Commission (“SEC”). The interim financial data as of March 31, 2017 is unaudited and is not necessarily indicative of the results for a full year. In the opinion of the Company’s management, the interim data includes only normal and recurring adjustments necessary for a fair statement of the Company’s financial results for the three months ended March 31, 2017 and 2016. Certain information and footnote disclosures normally included in annual financial statements prepared in accordance with U.S. GAAP have been condensed or omitted pursuant to SEC rules and regulations relating to interim financial statements. The accompanying condensed consolidated financial statements should be read in conjunction with the Company’s audited financial statements and notes thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2016 that has been filed with the SEC. Public Offering In February 2017, the Company completed a public offering of shares of its common stock, issuing a total of 2.9 million shares of common stock (including 0.5 million shares issued after exercise by the underwriters of their option to purchase additional shares) at an offering price of $17.00 per share. Certain existing stockholders of the Company also sold approximately 1.2 million shares of common stock in the offering. The Company received net proceeds of approximately $45.4 million, after deducting underwriting discounts and commissions of $2.9 million and offering expenses of $0.7 million payable by the Company. The Company did not receive any proceeds from the sale of shares by the selling stockholders. 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 disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenue and expenses during the reported period. Actual results could differ from those estimates. Significant Accounting Policies There have been no changes in the Company’s significant accounting policies for the three months ended March 31, 2017, as compared to the significant accounting policies described in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2016. Recent Accounting Pronouncements In May 2014, the Financial and Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2014-09, Revenue from Contracts with Customers. This standard will eliminate the transaction and industry specific revenue recognition guidance under current U.S. GAAP and replace it with a principles-based approach for determining revenue recognition. In December 2016, the FASB issued ASU 2016-20, Technical Corrections and Improvements to Topic 606 – Revenue from Contracts with Customers, to clarify the Codification or to correct unintended application of guidance. The new guidance is effective for annual and interim periods beginning after December 15, 2018. ASU 2014-09 allows for full retrospective adoption applied to all periods presented or modified retrospective adoption with the cumulative effect of initially applying the standard recognized at the date of initial application. In March 2016, the FASB issued ASU 2016-08, Principal versus Agent Considerations – Reporting Revenue Gross versus Net. This ASU clarifies the revenue recognition implementation guidance for preparers on certain aspects of principal versus agent consideration. The amendments in this ASU are effective for private companies and emerging growth companies beginning after December 15, 2018. The Company has performed a review of the requirements of the new guidance and has identified which of its revenue streams will be within the scope of ASU 2014-09. The Company is working through an adoption plan which includes a review of customer contracts, applying the five-step model of the new standard, to each revenue stream and comparing the results to its current accounting; an evaluation of the method of adoption; and assessing changes that might be necessary to information technology systems, processes, and internal controls to capture new data and address changes in financial reporting. Because of the nature of the work that remains, at this time the Company is unable to reasonably estimate the impact of adoption on its consolidated financial statements. In August 2015, the FASB issued ASU Interest-Imputation of Interest, to provide guidance on measurement of debt issuance costs associated with line-of-credit arrangements. ASU allows debt issuance costs associated with line-of-credit arrangements to be deferred and presented as an asset and subsequently amortized ratably over the term of the line-of-credit arrangement. The Company adopted ASU effective January 1, 2017. The adoption of this standard did not have a material effect on the Company’s financial statements In January 2016, the FASB issued ASU 2016-01, Recognition and Measurement of Financial Assets and Financial Liabilities, which addresses certain aspects of recognition, measurement, presentation, and disclosure of financial instruments. ASU 2016-01 is effective for fiscal years, and interim periods within those years, beginning after December 15, 2017, and early adoption is not permitted. The Company does not expect that adoption of ASU 2016-01 will have a significant impact on its consolidated financial statements. In February 2016, the FASB issued ASU 2016-02, Leases, which requires that lease arrangements longer than twelve months result in an entity recognizing an asset and liability. The updated guidance in this ASU are effective for private companies and emerging growth companies beginning after December 15, 2019. The Company is currently evaluating the impact of the updated guidance on its consolidated financial statements. In March 2016, the FASB issued ASU 2016-09, Compensation – Stock Compensation, which is intended to simplify several aspects of the accounting for share-based payment transactions, including the income tax consequences, classification of awards as either equity or liabilities, the estimation of forfeitures, shares withheld for taxes and classification of shares withheld for taxes on the statement of cash flows. As part of the adoption of this guidance the Company has elected to account for forfeitures of share-based awards as they occur. In June 2016, the FASB issued ASU 2016-13, Financial Instruments – Credit Losses to require the measurement of expected credit losses for financial instruments held at the reporting date based on historical experience, current conditions and reasonable forecasts. The main objective of this ASU is to provide financial statement users with more decision-useful information about the expected credit losses on financial instruments and other commitments to extend credit held by a reporting entity at each reporting date. This ASU is effective for private companies and emerging growth companies beginning after December 15, 2020; the ASU allows for early adoption as of the beginning of an interim or annual reporting period beginning after December 15, 2018. The Company is currently assessing the impact that this standard will have on its consolidated financial statements. In August 2016, the FASB issued ASU 2016-15, Statements of Cash Flows – Classifications of Certain Cash Receipts and Cash Payments to clarify how companies present and classify certain cash receipts and cash payments in the statement of cash flows. This ASU is effective for private companies and emerging growth companies beginning after December 15, 2018; the ASU allows for early adoption. The Company does not believe that adoption of ASU 2016-15 will have a significant impact on its consolidated financial statements. In January 2017, the FASB issued ASU 2017-01, Business Combinations – Clarifying the Definition of a Business, to clarify the definition of a business with the objective of adding guidance to assist entities with evaluating whether transactions should be accounted for as acquisitions (or dispositions) of assets or businesses. This ASU is effective for private companies and emerging growth companies beginning after December 15, 2018; the ASU allows for early adoption. The Company does not believe that adoption of ASU 2017-01 will have a significant impact on its consolidated financial statements. In January 2017, the FASB issued ASU 2017-04, This ASU is effective for private companies and emerging growth companies beginning after December 15, 2020; the ASU allows for early adoption. The Company does not believe that adoption of ASU 2017-04 will have a significant impact on its consolidated financial statements.

Composition of Certain Financia

Composition of Certain Financial Statement Items	3 Months Ended
	Mar. 31, 2017
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Composition of Certain Financial Statement Items	NOTE C. COMPOSITION OF CERTAIN FINANCIAL STATEMENT ITEMS Inventories March 31, December 31, (in thousands) 2017 2016 Finished goods $ 3,350 $ 3,562 Work in process 922 536 Raw materials 3,052 3,128 Total $ 7,324 $ 7,226 Property and Equipment March 31, December 31, (in thousands) 2017 2016 Furniture and office equipment $ 873 $ 873 Computer hardware and software 3,016 2,831 Laboratory equipment 4,537 4,336 Tooling and molds 1,512 1,512 Leasehold improvements 2,050 2,006 $ 11,988 $ 11,558 Less accumulated depreciation and amortization (5,991 ) (5,465 ) Property and equipment in progress 574 394 Total $ 6,571 $ 6,487 Depreciation and amortization expense was $0.5 million and $0.3 million on property and equipment during the three months ended March 31, 2017 and 2016, respectively. Intangible Assets March 31, December 31, (in thousands) 2017 2016 Technologies $ 9,700 $ 9,700 Trade name 500 500 $ 10,200 $ 10,200 Less accumulated amortization (538 ) (360 ) Total $ 9,662 $ 9,840 Amortization expense was $0.2 million and zero on intangible assets during the three months ended March 31, 2017 and 2016, respectively. Accrued Expenses March 31, December 31, (in thousands) 2017 2016 Compensation and commissions payable $ 5,402 $ 8,674 Royalty payable 1,720 1,851 Other accrued expenses 2,257 2,480 Total $ 9,379 $ 13,005

Liquidity and Business Risks

Liquidity and Business Risks	3 Months Ended
	Mar. 31, 2017
Equity [Abstract]
Liquidity and Business Risks	NOTE D. LIQUIDITY AND BUSINESS RISKS As of March 31, 2017, the Company had cash and cash equivalents of $65.2 million, short-term investments of $3.0 million and an accumulated deficit of $159.1 million. In the first quarter of 2017, the Company completed a public offering of shares of its common stock, issuing a total of 2.9 million shares of common stock (including 0.5 million shares issued after exercise by the underwriters of their option to purchase additional shares) at an offering price of $17.00 per share. Certain existing stockholders of the Company also sold approximately 1.2 million shares of common stock in the offering. The Company received net proceeds of $45.4 million, after deducting underwriting discounts and commissions of $2.9 million and offering expenses of $0.7 million payable by the Company. The Company did not receive any proceeds from the sale of shares by the selling stockholders. In March 2017, the Company entered into a loan and security agreement with Oxford Finance LLC. Under the terms of the loan and security agreement, the Company may borrow up to a total of $40.0 million in term loans in three tranches , subject to a borrowing base requirement. The first term loan of $13.5 million was borrowed immediately on March 31, 2017 by the Company of which was used to repay a portion of approximately $20.0 million in pre-existing outstanding indebtedness. Prior to its initial public offering (“IPO”), the Company financed its operations with a combination of revenue, private placements of convertible preferred securities and amounts borrowed under its credit facility. The Company expects that its cash and cash equivalents, short-term investments and anticipated revenue will be sufficient to fund its operations through at least the next 24 months.

Short-Term Investments

Short-Term Investments	3 Months Ended
	Mar. 31, 2017
Investments Debt And Equity Securities [Abstract]
SHORT-TERM INVESTMENTS	NOTE E. SHORT-TERM INVESTMENTS The Company determines the appropriate classification of its investments at the time of purchase and revaluates such determinations at each balance sheet date. Marketable securities are classified as held-to-maturity when the Company has the positive intent and ability to hold the securities to maturity. Marketable securities for which the Company does not have the intent or ability to hold to maturity are classified as available-for-sale. Marketable securities classified as available-for-sale are carried at fair market value, with the unrealized gains and losses included in the determination of comprehensive income and reported in stockholders’ equity. The following is a summary of the available-for-sale investments by type of instrument, which are included in short-term investments in the consolidated balance sheets as of March 31, 2017 and December 31, 2016. Unrealized Unrealized Gain in Losses in Accumulated Accumulated Other Other Amortized Comprehensive Comprehensive Estimated March 31, 2017 (in thousands) Cost Loss Loss Fair Value Commercial paper $ 750 $ — $ — $ 750 Corporate bonds 2,254 — (1 ) 2,253 Total available-for-sale securities $ 3,004 $ — $ (1 ) $ 3,003 Unrealized Unrealized Gain in Losses in Accumulated Accumulated Other Other Amortized Comprehensive Comprehensive Estimated December 31, 2016 (in thousands) Cost Loss Loss Fair Value Commercial paper $ 2,495 $ 2 $ — $ 2,497 Corporate bonds 4,099 — (2 ) 4,097 Foreign assets 4,250 1 — 4,251 Total available-for-sale securities $ 10,844 $ 3 $ (2 ) $ 10,845 Based on an evaluation of securities that have been in a loss position, the Company did not recognize any other-than-temporary impairment charges during the three months ended March 31, 2017. The Company considered various factors, including a credit and liquidity assessment of the underlying securities and the Company’s intent and ability to hold the underlying securities until the estimated date of recovery of its amortized cost. As of March 31, 2017 and December 31, 2016, available-for-sale maturities as noted in the table above mature in one year or less.

Fair Value Measurements

Fair Value Measurements	3 Months Ended
	Mar. 31, 2017
Fair Value Disclosures [Abstract]
Fair Value Measurements	NOTE F. FAIR VALUE MEASUREMENTS As of March 31, 2017 and as of December 31, 2016, the carrying amounts of cash and cash equivalents, receivables, accounts payable and accrued expenses approximated their estimated fair values because of the short-term nature of these financial instruments. Fair value is defined as the price that would be received upon the sale of an asset or paid to transfer a liability in an orderly transaction between market participants on the measurement date. Valuation techniques used to measure fair value maximize the use of observable inputs and minimize the use of unobservable inputs. Financial assets and liabilities carried at fair value are to be classified and disclosed in one of the following three categories: • Level 1: Quoted market prices in active markets for identical assets or liabilities. • Level 2: Includes other than Level 1 inputs that are observable, either directly or indirectly, such as quoted prices for similar assets or liabilities; quoted prices in markets that are not active; or other inputs for which all significant inputs are observable or can be corroborated by observable market data for substantially the full term of the asset or liabilities. • Level 3: Unobservable inputs that are supported by little or no market activities, which would require the Company to develop its own assumptions. Short-term Investments The following is a summary of available-for-sale investments by type of instrument measured at fair value on a recurring basis at March 31, 2017 and December 31, 2016. March 31, 2017 Level 1 Level 2 Level 3 Total Commercial paper $ — $ 750 $ — $ 750 Corporate bonds — 2,253 — 2,253 Total $ — $ 3,003 $ — $ 3,003 December 31, 2016 Level 1 Level 2 Level 3 Total Commercial paper $ — $ 2,497 $ — $ 2,497 Corporate bonds — 4,097 — 4,097 Foreign assets — 4,251 — 4,251 Total $ — $ 10,845 $ — $ 10,845 There were no transfers in or out of Level 1, Level 2 or Level 3 fair value measurement during the three months ended March 31, 2017. The Company has not experienced any significant realized gains or losses on its investments in the periods presented in the consolidated statements of operations and comprehensive loss.

Debt

Debt	3 Months Ended
	Mar. 31, 2017
Debt Disclosure [Abstract]
Debt	NOTE G. DEBT In December 2013, the Company entered into an amended and restated credit facility (the “Prior Credit Facility”) with Oxford Finance LLC (“Oxford”). Under the Prior Credit Facility, the Company borrowed $20.0 million at a fixed rate of 9.40%. The Prior Credit Facility was scheduled to mature and all amounts borrowed thereunder were due on December 1, 2018. In February 2017, the Company entered into an amendment to the amended and restated loan and security agreement to allow principal payments due on February 1, 2017 and March 1, 2017 to be deferred until March 15, 2017. In March 2017, the principal payments were deferred again during renegotiations with Oxford. In March 2017, the Company entered into a loan and security agreement (the “Loan Agreement”) providing for a new credit facility (the “New Credit Facility”). Under the terms of the New Credit Facility, the Company may borrow from the lenders (collectively the “Lenders”) up to a total of $40.0 million in term loans in three tranches (each, a “Term Loan” or, collectively, “Term Loans”) , subject to a borrowing base requirement (the “Revolving Line of Credit”). The first Term Loan of $13.5 million was borrowed immediately, in addition to $8.0 million under the Revolving Line of Credit, and used to repay approximately $20.0 million of then outstanding indebtedness, which constituted all amounts outstanding related to the Prior Credit Facility, together with the final payment fee totaling $1.2 million. The Credit Facility was accounted for as a modification of debt under applicable accounting guidance. The second Term Loan of up to $10.0 million is available beginning on the earlier of the completion of a future merger, consolidation or acquisition in which the borrowings would be used by the Company to pay the purchase price or November 1, 2017 (if certain trailing 12-month revenues are met) and ending on December 31, 2017. The third Term Loan of up to $16.5 million is available beginning on the earlier of the completion of a future merger, consolidation or acquisition in which the borrowings would be used by the Company to pay the purchase price or the occurrence of certain trailing 12-month revenues and ending on March 31, 2018. The borrowings under the second and third Term Loans must be used to fund a merger, consolidation or acquisition or may be used for working capital so long as the Company’s trailing 12-month revenues meet certain amounts. The third Term Loan cannot be made prior to the funding of the second Term Loan, or if no second Term Loan is made, January 1, 2018. The Term Loans mature and all amounts borrowed under the New Each Term Loan bears interest at a floating per annum rate equal to the greater of (1) 7.95% and (2) the sum of (i) the greater of (A) the 30-day U.S. LIBOR rate reported in The Wall Street Journal plus The Wall Street Journal plus In addition to principal and interest payments, the Company is required under the New Credit Facility New New The Company’s obligations under the New Credit Facility Loan Agreement Loan Agreement The Loan Agreement contains affirmative and negative covenants applicable to the Company and any subsidiaries and events of default, in each case subject to grace periods, thresholds and materiality qualifiers, as more fully described in the Loan Agreement. The affirmative covenants include, among others, covenants requiring the Company to maintain its legal existence and material governmental approvals, deliver certain financial reports and maintain insurance coverage. The negative covenants include, among others, restrictions on the Company incurring additional indebtedness, engaging in mergers, consolidations or acquisitions, paying dividends or making other distributions, making investments, creating liens, selling assets, and suffering a change in control. The events of default include, among other things, the Company’s failure to pay any amounts due under the New New Credit Facility New Credit Facility The Company was in compliance with all required covenants as of March 31, 2017 and December 31, 2016. As of March 31, 2017 and December 31, 2016, the Company has borrowed and had outstanding $13.5 million and $20.0 million of term loan debt under the New Credit Facility and Prior Credit Facility, respectively. As of March 31, 2017, the Company had borrowed $8.0 million of the available $10.0 million under the Revolving Line of Credit under the New Credit Facility. As of March 31, 2017 and the carrying amount of debt approximated fair value because the interest rate approximates current market rates of interest available in the market. The fair value of the Company’s debt is considered a Level 3 measurement. Assuming a 60-month amortization period as stated in the New (in thousands) 2017 $ — 2018 — 2019 3,375 2020 4,500 2021 4,500 2022 1,125 $ 13,500

Stockholders' Equity

Stockholders' Equity	3 Months Ended
	Mar. 31, 2017
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stockholders' Equity	NOTE H. STOCKHOLDERS’ EQUITY Preferred Stock The Company’s amended and restated certificate of incorporation authorizes 10.0 million shares of preferred stock. As of March 31, 2017, no . Common Stock T he Company’s amended and restated certificate of incorporation authorizes 2015 Incentive Award Plan In December 2014, the Company’s Board of Directors adopted, and in January 2015 the Company’s stockholders approved, the Entellus Medical, Inc. 2015 Incentive Award Plan (the “2015 Plan”). The 2015 Plan became effective in connection with the IPO, at which time the Company ceased making awards under the Entellus Medical, Inc. 2006 Stock Incentive Plan (“2006 Plan). Under the 2015 Plan, the Company may grant stock options, stock appreciation rights, restricted stock, restricted stock units and certain other awards to individuals who are employees, officers, directors or consultants of the Company. A total of 1,346,570 shares of common stock were initially reserved for issuance under the 2015 Plan. In addition, the number of shares available for issuance under the 2015 Plan is annually increased by an amount equal to the lesser of (A) 875,000 shares, (B) 4% of the outstanding shares of the Company’s common stock as of the last day of the Company’s immediately preceding fiscal year or, an amount determined by the Company’s Board of Directors. Furthermore, any shares subject to awards granted under the 2006 Plan which terminate, expire or lapse without the delivery of shares to the holder thereof become available under the 2015 Plan. In the first quarter of 2017 and 2016, in accordance with this “evergreen” provision, the number of shares available under the 2015 Plan was increased in the amount of 756,339 shares and 751,750 shares, respectively. As of March 31, 2017, 959,294 shares of common stock were available for issuance under the 2015 Plan. Stock Options A summary of the Company’s stock option activity and related information is as follows: March 31, 2017 Weighted average Aggregate Weighted remaining intrinsic average contractual value (shares in thousands) Options exercise price term ($000) Outstanding, beginning of period 3,349 $ 13.06 7.6 years $ 21,863 Granted 427 16.96 Exercised (123 ) 5.46 Cancelled — — Forfeited (203 ) 16.54 Outstanding, end of period 3,450 $ 13.61 7.9 years $ 8,608 Exercisable 1,528 $ 10.82 6.8 years $ 7,102 The aggregate pre-tax intrinsic value of options exercised was $1.4 million and $0.3 million for the three months ended March 31, 2017 and 2016, respectively. The aggregate pre-tax intrinsic value was calculated as the difference between the exercise prices of the underlying options and the estimated fair value of the common stock on the date of exercise or March 31, 2017 and 2016, as applicable. During the three months ended March 31, 2017 and 2016, the fair value of shares vesting was $1.5 million and $1.0 million, respectively. The total cash received upon the exercise of options was $0.7 million and less than $0.1 million during the three months ended March 31, 2017 and 2016, respectively. Restricted Stock Units The Company grants time-based restricted stock units (RSUs) to executive officers and other senior employees generally vesting over a four-year period. In addition, certain key management members typically receive RSUs upon commencement of employment and may receive them annually in conjunction with the Company’s performance review. The grant date fair value of the RSU awards is determined using the closing stock price of the Company’s common stock on the day prior to the date of the grant. Restricted stock unit activity during the three months ended March 31, 2017 is summarized below: March 31, 2017 Weighted average grant date (shares in thousands) RSUs fair value Outstanding, beginning of period 12 $ 16.99 Granted 151 Released (3 ) Forfeited/expired (8 ) Outstanding, end of period 152 $ 17.80 Employee Stock Purchase Plan In December 2014, the Company’s Board of Directors adopted, and in January 2015 the Company’s stockholders approved, the Entellus Medical, Inc. 2015 Employee Stock Purchase Plan (“ESPP”). Under the ESPP, the Company has set two six-month offering periods during each calendar year, one beginning January 1 and ending on June 30, and the other beginning July 1 and ending on December 31, during which employees can choose to have up to 20% of their eligible compensation withheld to purchase less than 2,000 shares of the Company’s common stock during each offering period. The purchase price of the shares is 85% of the market price on the first or last trading day of the offering period, whichever is lower. A total of 200,000 shares of common stock were initially reserved for issuance under the ESPP. In addition, the number of shares of common stock available for issuance under the ESPP will be annually increased on the first day of each fiscal year during the term of the ESPP, beginning with the 2016 fiscal year, by an amount equal to the lesser of (A) 1% of the shares of the Company’s common stock outstanding on the date of the adoption of the plan or (B) a lesser amount determined by the Company’s Board of Directors. In the first quarters of 2016 and 2017, in accordance with this “evergreen” provision, the number of shares available for grant under the ESPP increased in the amount of 16,488 shares and 16,488 shares, respectively, resulting in a total of 232,976 shares of common stock reserved for issuance under the ESPP. During 2016, 35,962 shares were issued resulting in a total of 197,014 shares of common stock remaining for issuance under the ESPP. During the three months ended March 31, 2016 and 2017 the Company did not issue shares of its common stock to participants under the ESPP. The Company recognized less than $0.1 million in stock-based compensation related to the ESPP during the three months ended March 31, 2016 and 2017, respectively.

Stock Based Compensation Expens

Stock Based Compensation Expense	3 Months Ended
	Mar. 31, 2017
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock Based Compensation Expense	NOTE I. STOCK-BASED COMPENSATION EXPENSE Stock-based compensation expense is reflected in the condensed consolidated statement of operations and comprehensive loss for the three months ended March 31, 2017 and 2016, as follows: Three Months Ended March 31, (in thousands) 2017 2016 Cost of goods sold $ 33 $ 22 Selling and marketing 619 448 Research and development 221 124 General and administrative 941 611 Total $ 1,814 $ 1,205 At March 31, 2017, there was approximately $14.5 million, $2.5 million and $0.1 million of unrecognized stock-based compensation expense related to unvested stock options, RSUs and ESPP awards, respectively, which the Company expects to recognize over the remaining weighted-average vesting period of approximately 2.6 years, 3.7 years and 0.3 years, respectively. If there are any modifications or cancellations of the underlying unvested securities, the Company may be required to accelerate, increase or cancel any remaining unearned stock-based compensation expense. Future stock-based compensation expense and unearned stock-based compensation will increase to the extent that the Company grants additional share-based awards. The Company estimates the fair value of stock-based compensation on the date of grant using the Black-Scholes option-pricing model. The Black-Scholes model determines the fair value of stock-based payment awards based on the fair market value of the Company’s common stock on the date of grant and is affected by assumptions regarding a number of highly complex and subjective variables. These variables include, but are not limited to, the fair market value of the Company’s common stock, volatility over the expected term of the awards and actual and projected employee stock option exercise behaviors. The Company has opted to use the “simplified method” for estimating the expected term of options, whereby the expected term equals the arithmetic average of the vesting term and the original contractual term of the option. Due to our limited operating history and company-specific historical and implied volatility data, we have based our estimate of expected volatility on the blended historical volatility of a group of similar companies that are publicly traded and our historical volatility. The fair value of the options granted to employees or directors during the three months ended March 31, 2017 and 2016 was estimated as of the grant date using the Black-Scholes model assuming the weighted average assumptions listed in the following table: Three Months Ended March 31, 2017 2016 Expected life in years 6.3 6.0 Risk-free interest rate 2.1%-2.2 % 1.5%-1.9 % Expected dividend yield 0 % 0 % Expected volatility 52%-54 % 50%-51 % Weighted average fair value $ 8.89 $ 8.22 The fair value of the ESPP options granted to employees during the three months ended March 31, 2017 and 2016 was estimated as of the grant date using the Black-Scholes model assuming the weighted average assumptions listed in the following table: Three Months Ended March 31, 2017 2016 Expected life in years 0.5 0.5 Risk-free interest rate 0.6 % 0.5 % Expected dividend yield 0 % 0 % Expected volatility 36 % 54 % Weighted average fair value $ 4.75 $ 5.15

Income Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2017
Income Tax Disclosure [Abstract]
Income Taxes	NOTE J. INCOME TAXES The Company did not record a federal, state or foreign income tax benefit for its losses for the three months ended March 31, 2017 and 2016 due to its conclusion that a valuation allowance is required against its net deferred tax assets excluding the deferred tax liability related to its tax deductible goodwill acquired in connection with the XeroGel acquisition.

Earnings Per Share

Earnings Per Share	3 Months Ended
	Mar. 31, 2017
Earnings Per Share [Abstract]
Earnings Per Share	NOTE K. EARNINGS PER SHARE Basic net loss per share is computed by dividing the net loss by the weighted average number of shares of common stock outstanding during the period. Diluted net loss per share is computed by dividing the net loss by the weighted average number of shares of common stock and dilutive potential shares of common stock outstanding during the period. Because the Company has reported a net loss for all periods presented, diluted net loss per share is the same as basic net loss per share for those periods as all potentially dilutive shares consisting of restricted stock units, stock options, warrants and common stock ESPP were antidilutive in those periods. The following table sets forth the computation of the Company’s net loss per share: Three Months Ended March 31, (in thousands) 2017 2016 Net loss $ (8,338 ) $ (6,872 ) Weighted average common stock outstanding 20,876 18,801 Net loss per share, basic and diluted $ (0.40 ) $ (0.37 ) The following potentially dilutive securities outstanding have been excluded from the computations of diluted earnings per share because such securities have an antidilutive impact due to losses reported: March 31, (in thousands) 2017 2016 Common stock warrants 38 38 Common stock options 3,450 2,939 Restricted stock units 152 12 Common stock ESPP 28 19 Total 3,668 3,008

Commitments and Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2017
Commitments And Contingencies Disclosure [Abstract]
Commitments and Contingencies	NOTE L. COMMITMENTS AND CONTINGENCIES Operating Leases As of March 31, 2017, the Company has three leased facilities under operating lease agreements. The Company entered into a 41-month lease in February 2012, effective April 1, 2012, for its manufacturing facility and corporate headquarters. The Company entered into a 50-month lease on June 30, 2014, effective July 1, 2014, for additional distribution space in a second facility. On February 26, 2015, the Company exercised its right to extend the lease term of its manufacturing and corporate facility for an additional three years through August 2018. On June 30, 2015, the Company entered into amendments to each lease agreement, among other things, to expand the space occupied by the Company at the property at which the Company’s corporate headquarters are located, and to extend the term of each lease agreement through June 2021, with an option to extend for an additional term through June 2024. Rental payments on operating leases are charged to expense on a straight-line basis over the period of the lease. These lease agreements require the Company to pay executory costs such as real estate taxes, insurance and repairs, and includes renewal and escalation clauses. In connection with the XeroGel acquisition, the Company assumed a lease agreement for manufacturing facility space in Hayward, California through August 31, 2017. Rental payments on operating leases are charged to expense on a straight-line basis over the period of the lease. This lease agreement requires the Company to pay executory costs such, as real estate taxes, insurance and repairs, and includes renewal and escalation clauses. Total lease expense was approximately $0.2 million and $0.1 million for the three months ended March 31, 2017 and 2016, respectively. Other Commitments In June 2016, the Company entered into an Amended and Restated Fiagon NA Distribution Agreement (the “Distribution Agreement”) with Fiagon NA Corporation in which the Company was granted exclusive distribution rights in the United States and Canada for Fiagon Image Guidance (“IGS”) Systems and certain components, parts and related ancillary products i) to hospitals, ii) to ENT physicians in the office, clinic, and surgery centers, and iii) under ENT healthcare system contracts. The terms of the Distribution Agreement require the Company to purchase minimum quantities of Fiagon IGS units and certain other disposable products through August 9, 2020 in order for the Company to retain exclusive distribution rights.

Summary of Significant Accoun18

Summary of Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2017
Accounting Policies [Abstract]
Basis of Preparation	Basis of Preparation The financial statements have been prepared in accordance with U.S. generally accepted accounting principles (“U.S. GAAP”) and pursuant to the rules and regulations of the United States Securities and Exchange Commission (“SEC”). The interim financial data as of March 31, 2017 is unaudited and is not necessarily indicative of the results for a full year. In the opinion of the Company’s management, the interim data includes only normal and recurring adjustments necessary for a fair statement of the Company’s financial results for the three months ended March 31, 2017 and 2016. Certain information and footnote disclosures normally included in annual financial statements prepared in accordance with U.S. GAAP have been condensed or omitted pursuant to SEC rules and regulations relating to interim financial statements. The accompanying condensed consolidated financial statements should be read in conjunction with the Company’s audited financial statements and notes thereto included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2016 that has been filed with the SEC.
Public Offering	Public Offering In February 2017, the Company completed a public offering of shares of its common stock, issuing a total of 2.9 million shares of common stock (including 0.5 million shares issued after exercise by the underwriters of their option to purchase additional shares) at an offering price of $17.00 per share. Certain existing stockholders of the Company also sold approximately 1.2 million shares of common stock in the offering. The Company received net proceeds of approximately $45.4 million, after deducting underwriting discounts and commissions of $2.9 million and offering expenses of $0.7 million payable by the Company. The Company did not receive any proceeds from the sale of shares by the selling stockholders.
Use of Estimates	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 disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenue and expenses during the reported period. Actual results could differ from those estimates.
Recent Accounting Pronouncements	Recent Accounting Pronouncements In May 2014, the Financial and Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2014-09, Revenue from Contracts with Customers. This standard will eliminate the transaction and industry specific revenue recognition guidance under current U.S. GAAP and replace it with a principles-based approach for determining revenue recognition. In December 2016, the FASB issued ASU 2016-20, Technical Corrections and Improvements to Topic 606 – Revenue from Contracts with Customers, to clarify the Codification or to correct unintended application of guidance. The new guidance is effective for annual and interim periods beginning after December 15, 2018. ASU 2014-09 allows for full retrospective adoption applied to all periods presented or modified retrospective adoption with the cumulative effect of initially applying the standard recognized at the date of initial application. In March 2016, the FASB issued ASU 2016-08, Principal versus Agent Considerations – Reporting Revenue Gross versus Net. This ASU clarifies the revenue recognition implementation guidance for preparers on certain aspects of principal versus agent consideration. The amendments in this ASU are effective for private companies and emerging growth companies beginning after December 15, 2018. The Company has performed a review of the requirements of the new guidance and has identified which of its revenue streams will be within the scope of ASU 2014-09. The Company is working through an adoption plan which includes a review of customer contracts, applying the five-step model of the new standard, to each revenue stream and comparing the results to its current accounting; an evaluation of the method of adoption; and assessing changes that might be necessary to information technology systems, processes, and internal controls to capture new data and address changes in financial reporting. Because of the nature of the work that remains, at this time the Company is unable to reasonably estimate the impact of adoption on its consolidated financial statements. In August 2015, the FASB issued ASU Interest-Imputation of Interest, to provide guidance on measurement of debt issuance costs associated with line-of-credit arrangements. ASU allows debt issuance costs associated with line-of-credit arrangements to be deferred and presented as an asset and subsequently amortized ratably over the term of the line-of-credit arrangement. The Company adopted ASU effective January 1, 2017. The adoption of this standard did not have a material effect on the Company’s financial statements In January 2016, the FASB issued ASU 2016-01, Recognition and Measurement of Financial Assets and Financial Liabilities, which addresses certain aspects of recognition, measurement, presentation, and disclosure of financial instruments. ASU 2016-01 is effective for fiscal years, and interim periods within those years, beginning after December 15, 2017, and early adoption is not permitted. The Company does not expect that adoption of ASU 2016-01 will have a significant impact on its consolidated financial statements. In February 2016, the FASB issued ASU 2016-02, Leases, which requires that lease arrangements longer than twelve months result in an entity recognizing an asset and liability. The updated guidance in this ASU are effective for private companies and emerging growth companies beginning after December 15, 2019. The Company is currently evaluating the impact of the updated guidance on its consolidated financial statements. In March 2016, the FASB issued ASU 2016-09, Compensation – Stock Compensation, which is intended to simplify several aspects of the accounting for share-based payment transactions, including the income tax consequences, classification of awards as either equity or liabilities, the estimation of forfeitures, shares withheld for taxes and classification of shares withheld for taxes on the statement of cash flows. As part of the adoption of this guidance the Company has elected to account for forfeitures of share-based awards as they occur. In June 2016, the FASB issued ASU 2016-13, Financial Instruments – Credit Losses to require the measurement of expected credit losses for financial instruments held at the reporting date based on historical experience, current conditions and reasonable forecasts. The main objective of this ASU is to provide financial statement users with more decision-useful information about the expected credit losses on financial instruments and other commitments to extend credit held by a reporting entity at each reporting date. This ASU is effective for private companies and emerging growth companies beginning after December 15, 2020; the ASU allows for early adoption as of the beginning of an interim or annual reporting period beginning after December 15, 2018. The Company is currently assessing the impact that this standard will have on its consolidated financial statements. In August 2016, the FASB issued ASU 2016-15, Statements of Cash Flows – Classifications of Certain Cash Receipts and Cash Payments to clarify how companies present and classify certain cash receipts and cash payments in the statement of cash flows. This ASU is effective for private companies and emerging growth companies beginning after December 15, 2018; the ASU allows for early adoption. The Company does not believe that adoption of ASU 2016-15 will have a significant impact on its consolidated financial statements. In January 2017, the FASB issued ASU 2017-01, Business Combinations – Clarifying the Definition of a Business, to clarify the definition of a business with the objective of adding guidance to assist entities with evaluating whether transactions should be accounted for as acquisitions (or dispositions) of assets or businesses. This ASU is effective for private companies and emerging growth companies beginning after December 15, 2018; the ASU allows for early adoption. The Company does not believe that adoption of ASU 2017-01 will have a significant impact on its consolidated financial statements. In January 2017, the FASB issued ASU 2017-04, This ASU is effective for private companies and emerging growth companies beginning after December 15, 2020; the ASU allows for early adoption. The Company does not believe that adoption of ASU 2017-04 will have a significant impact on its consolidated financial statements.

Composition of Certain Financ19

Composition of Certain Financial Statement Items (Tables)	3 Months Ended
	Mar. 31, 2017
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Schedule of Inventories	Inventories March 31, December 31, (in thousands) 2017 2016 Finished goods $ 3,350 $ 3,562 Work in process 922 536 Raw materials 3,052 3,128 Total $ 7,324 $ 7,226
Schedule of Property and Equipment	Property and Equipment March 31, December 31, (in thousands) 2017 2016 Furniture and office equipment $ 873 $ 873 Computer hardware and software 3,016 2,831 Laboratory equipment 4,537 4,336 Tooling and molds 1,512 1,512 Leasehold improvements 2,050 2,006 $ 11,988 $ 11,558 Less accumulated depreciation and amortization (5,991 ) (5,465 ) Property and equipment in progress 574 394 Total $ 6,571 $ 6,487
Schedule of Intangible Assets	Intangible Assets March 31, December 31, (in thousands) 2017 2016 Technologies $ 9,700 $ 9,700 Trade name 500 500 $ 10,200 $ 10,200 Less accumulated amortization (538 ) (360 ) Total $ 9,662 $ 9,840
Schedule of Accrued Expenses	Accrued Expenses March 31, December 31, (in thousands) 2017 2016 Compensation and commissions payable $ 5,402 $ 8,674 Royalty payable 1,720 1,851 Other accrued expenses 2,257 2,480 Total $ 9,379 $ 13,005

Short-Term Investments (Tables)

Short-Term Investments (Tables)	3 Months Ended
	Mar. 31, 2017
Investments Debt And Equity Securities [Abstract]
Summary of Investments by Type of Instrument	The following is a summary of the available-for-sale investments by type of instrument, which are included in short-term investments in the consolidated balance sheets as of March 31, 2017 and December 31, 2016. Unrealized Unrealized Gain in Losses in Accumulated Accumulated Other Other Amortized Comprehensive Comprehensive Estimated March 31, 2017 (in thousands) Cost Loss Loss Fair Value Commercial paper $ 750 $ — $ — $ 750 Corporate bonds 2,254 — (1 ) 2,253 Total available-for-sale securities $ 3,004 $ — $ (1 ) $ 3,003 Unrealized Unrealized Gain in Losses in Accumulated Accumulated Other Other Amortized Comprehensive Comprehensive Estimated December 31, 2016 (in thousands) Cost Loss Loss Fair Value Commercial paper $ 2,495 $ 2 $ — $ 2,497 Corporate bonds 4,099 — (2 ) 4,097 Foreign assets 4,250 1 — 4,251 Total available-for-sale securities $ 10,844 $ 3 $ (2 ) $ 10,845

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	3 Months Ended
	Mar. 31, 2017
Fair Value Disclosures [Abstract]
Summary of Available-for-sale Investments at Fair Value on Recurring Basis	The following is a summary of available-for-sale investments by type of instrument measured at fair value on a recurring basis at March 31, 2017 and December 31, 2016. March 31, 2017 Level 1 Level 2 Level 3 Total Commercial paper $ — $ 750 $ — $ 750 Corporate bonds — 2,253 — 2,253 Total $ — $ 3,003 $ — $ 3,003 December 31, 2016 Level 1 Level 2 Level 3 Total Commercial paper $ — $ 2,497 $ — $ 2,497 Corporate bonds — 4,097 — 4,097 Foreign assets — 4,251 — 4,251 Total $ — $ 10,845 $ — $ 10,845

Debt (Tables)

Debt (Tables)	3 Months Ended
	Mar. 31, 2017
New Credit Facility [Member]
Debt Instrument [Line Items]
Schedule of Principal Payments under Term Loan	Assuming a 60-month amortization period as stated in the New (in thousands) 2017 $ — 2018 — 2019 3,375 2020 4,500 2021 4,500 2022 1,125 $ 13,500

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	3 Months Ended
	Mar. 31, 2017
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Summary of Stock Option Activity and Related Information	A summary of the Company’s stock option activity and related information is as follows: March 31, 2017 Weighted average Aggregate Weighted remaining intrinsic average contractual value (shares in thousands) Options exercise price term ($000) Outstanding, beginning of period 3,349 $ 13.06 7.6 years $ 21,863 Granted 427 16.96 Exercised (123 ) 5.46 Cancelled — — Forfeited (203 ) 16.54 Outstanding, end of period 3,450 $ 13.61 7.9 years $ 8,608 Exercisable 1,528 $ 10.82 6.8 years $ 7,102
Summary of Restricted Stock Units Activity	Restricted stock unit activity during the three months ended March 31, 2017 is summarized below: March 31, 2017 Weighted average grant date (shares in thousands) RSUs fair value Outstanding, beginning of period 12 $ 16.99 Granted 151 Released (3 ) Forfeited/expired (8 ) Outstanding, end of period 152 $ 17.80

Stock Based Compensation Expe24

Stock Based Compensation Expense (Tables)	3 Months Ended
	Mar. 31, 2017
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Summary of Stock-based Compensation Expense in Condensed Consolidated Statement of Operations and Comprehensive Loss	Stock-based compensation expense is reflected in the condensed consolidated statement of operations and comprehensive loss for the three months ended March 31, 2017 and 2016, as follows: Three Months Ended March 31, (in thousands) 2017 2016 Cost of goods sold $ 33 $ 22 Selling and marketing 619 448 Research and development 221 124 General and administrative 941 611 Total $ 1,814 $ 1,205
Summary of Weighted Average Assumptions Used in Black-Scholes Model in Estimating Fair Value of Option Granted	The fair value of the options granted to employees or directors during the three months ended March 31, 2017 and 2016 was estimated as of the grant date using the Black-Scholes model assuming the weighted average assumptions listed in the following table: Three Months Ended March 31, 2017 2016 Expected life in years 6.3 6.0 Risk-free interest rate 2.1%-2.2 % 1.5%-1.9 % Expected dividend yield 0 % 0 % Expected volatility 52%-54 % 50%-51 % Weighted average fair value $ 8.89 $ 8.22
Summary of Weighted Average Assumptions Used in Black-Scholes Model in Estimating Fair Value of ESPP Option Granted	The fair value of the ESPP options granted to employees during the three months ended March 31, 2017 and 2016 was estimated as of the grant date using the Black-Scholes model assuming the weighted average assumptions listed in the following table: Three Months Ended March 31, 2017 2016 Expected life in years 0.5 0.5 Risk-free interest rate 0.6 % 0.5 % Expected dividend yield 0 % 0 % Expected volatility 36 % 54 % Weighted average fair value $ 4.75 $ 5.15

Earnings Per Share (Tables)

Earnings Per Share (Tables)	3 Months Ended
	Mar. 31, 2017
Earnings Per Share [Abstract]
Schedule of Net Loss Per Share	The following table sets forth the computation of the Company’s net loss per share: Three Months Ended March 31, (in thousands) 2017 2016 Net loss $ (8,338 ) $ (6,872 ) Weighted average common stock outstanding 20,876 18,801 Net loss per share, basic and diluted $ (0.40 ) $ (0.37 )
Schedule of Antidilutive Securities Outstanding Excluded from Computation of Earnings Per Share	The following potentially dilutive securities outstanding have been excluded from the computations of diluted earnings per share because such securities have an antidilutive impact due to losses reported: March 31, (in thousands) 2017 2016 Common stock warrants 38 38 Common stock options 3,450 2,939 Restricted stock units 152 12 Common stock ESPP 28 19 Total 3,668 3,008

Organization - Additional Infor

Organization - Additional Information (Detail)	3 Months Ended
	Mar. 31, 2017Segment
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Number of reportable segments	1

Summary of Significant Accoun27

Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($) $ / shares in Units, shares in Millions	1 Months Ended	3 Months Ended
	Feb. 28, 2017	Mar. 31, 2017
Accounting Policies [Line Items]
Proceeds from public offering, net of issuance costs		$ 45,361,000
Secondary Public Offering [Member]
Accounting Policies [Line Items]
Common stock, shares issued	2.9	2.9
Common stock offering price per share	$ 17	$ 17
Proceeds from public offering, net of issuance costs	$ 45,400,000	$ 45,400,000
Underwriting discounts and commissions	2,900,000	2,900,000
Public offering expenses	$ 700,000	$ 700,000
Additional Share Purchase by Underwriters [Member]
Accounting Policies [Line Items]
Common stock, shares issued	0.5	0.5
Sale by Certain Existing Shareholders [Member]
Accounting Policies [Line Items]
Common stock sold by certain existing stockholders	1.2	1.2
Proceeds from sale of shares by existing selling stockholders	$ 0	$ 0

Composition of Certain Financ28

Composition of Certain Financial Statement Items - Schedule of Inventories (Detail) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Inventory Disclosure [Abstract]
Finished goods	$ 3,350	$ 3,562
Work in process	922	536
Raw materials	3,052	3,128
Total	$ 7,324	$ 7,226

Composition of Certain Financ29

Composition of Certain Financial Statement Items - Schedule of Property and Equipment (Detail) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Property, Plant and Equipment [Line Items]
Property plant and equipment, Gross	$ 11,988	$ 11,558
Less accumulated depreciation and amortization	(5,991)	(5,465)
Property and equipment in progress	574	394
Total	6,571	6,487
Furniture and Office Equipment [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment, Gross	873	873
Computer Hardware and Software [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment, Gross	3,016	2,831
Laboratory Equipment [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment, Gross	4,537	4,336
Tooling and Molds [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment, Gross	1,512	1,512
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment, Gross	$ 2,050	$ 2,006

Composition of Certain Financ30

Composition of Certain Financial Statement Items - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Property Plant And Equipment [Abstract]
Depreciation and amortization on property and equipment	$ 0.5	$ 0.3
Amortization expenses on intangible assets	$ 0.2	$ 0

Composition of Certain Financ31

Composition of Certain Financial Statement Items - Schedule of Intangible Assets (Detail) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Finite Lived Intangible Assets [Line Items]
Intangible assets, gross	$ 10,200	$ 10,200
Less accumulated amortization	(538)	(360)
Total	9,662	9,840
Technologies [Member]
Finite Lived Intangible Assets [Line Items]
Intangible assets, gross	9,700	9,700
Trade Names [Member]
Finite Lived Intangible Assets [Line Items]
Intangible assets, gross	$ 500	$ 500

Composition of Certain Financ32

Composition of Certain Financial Statement Items - Schedule of Accrued Expenses (Detail) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Payables And Accruals [Abstract]
Compensation and commissions payable	$ 5,402	$ 8,674
Royalty payable	1,720	1,851
Other accrued expenses	2,257	2,480
Total	$ 9,379	$ 13,005

Liquidity and Business Risks -

Liquidity and Business Risks - Additional Information (Detail) $ / shares in Units, shares in Millions	1 Months Ended		3 Months Ended
	Mar. 31, 2017USD ($)Tranches$ / shares	Feb. 28, 2017USD ($)$ / sharesshares	Mar. 31, 2017USD ($)$ / sharesshares	Dec. 31, 2016USD ($)	Mar. 31, 2016USD ($)	Dec. 31, 2015USD ($)
Subsidiary, Sale of Stock [Line Items]
Cash and cash equivalents	$ 65,189,000		$ 65,189,000	$ 21,417,000	$ 23,766,000	$ 28,548,000
Short-term investments	3,003,000		3,003,000	10,845,000
Accumulated deficit	(159,126,000)		(159,126,000)	$ (150,788,000)
Proceeds from issuance of common stock, net of issuance costs			45,361,000
Line of credit facility, repayment of amount outstanding	$ 20,000,000
Term Loans [Member]
Subsidiary, Sale of Stock [Line Items]
Number of tranches | Tranches	3
Term Loans [Member] | Maximum [Member]
Subsidiary, Sale of Stock [Line Items]
Amount borrowed under facility	$ 40,000,000		40,000,000
First Term Loan [Member]
Subsidiary, Sale of Stock [Line Items]
Amount borrowed under facility	13,500,000		13,500,000
Revolving Line of Credit [Member]
Subsidiary, Sale of Stock [Line Items]
Line of credit facility, amount outstanding	8,000,000		8,000,000
Revolving Line of Credit [Member] | Maximum [Member]
Subsidiary, Sale of Stock [Line Items]
Line of credit facility, maximum borrowing capacity	10,000,000		10,000,000
Line of credit facility, additional borrowing capacity on meeting future requirement	$ 2,000,000		$ 2,000,000
Secondary Public Offering [Member]
Subsidiary, Sale of Stock [Line Items]
Common stock, shares issued | shares		2.9	2.9
Common stock offering price per share | $ / shares	$ 17	$ 17	$ 17
Proceeds from issuance of common stock, net of issuance costs		$ 45,400,000	$ 45,400,000
Underwriting discounts and commissions		2,900,000	2,900,000
Public offering expenses		$ 700,000	$ 700,000
Additional Share Purchase by Underwriters [Member]
Subsidiary, Sale of Stock [Line Items]
Common stock, shares issued | shares		0.5	0.5
Sale by Certain Existing Shareholders [Member]
Subsidiary, Sale of Stock [Line Items]
Common stock sold by certain existing stockholders | shares		1.2	1.2
Proceeds from sale of shares by existing selling stockholders		$ 0	$ 0

Short-term Investments - Summar

Short-term Investments - Summary of Investments by Type of Instrument (Detail) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	$ 3,004	$ 10,844
Unrealized Gain in Accumulated Other Comprehensive Loss		3
Unrealized Losses in Accumulated Other Comprehensive Loss	(1)	(2)
Estimated Fair Value	3,003	10,845
Short-term Investments [Member] | Commercial Paper [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	750	2,495
Unrealized Gain in Accumulated Other Comprehensive Loss		2
Estimated Fair Value	750	2,497
Short-term Investments [Member] | Corporate Bonds [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	2,254	4,099
Unrealized Losses in Accumulated Other Comprehensive Loss	(1)	(2)
Estimated Fair Value	$ 2,253	4,097
Short-term Investments [Member] | Foreign Assets [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost		4,250
Unrealized Gain in Accumulated Other Comprehensive Loss		1
Estimated Fair Value		$ 4,251

Short-term Investments - Additi

Short-term Investments - Additional Information (Detail)	3 Months Ended
	Mar. 31, 2017USD ($)
Investments Debt And Equity Securities [Abstract]
Other-than-temporary impairment charges	$ 0

Fair Value Measurements - Summa

Fair Value Measurements - Summary of Available-for-sale Investments at Fair Value on Recurring Basis (Detail) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale investments	$ 3,003	$ 10,845
Fair Value, Measurements, Recurring [Member]
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale investments	3,003	10,845
Fair Value, Measurements, Recurring [Member] | Commercial Paper [Member]
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale investments	750	2,497
Fair Value, Measurements, Recurring [Member] | Corporate Bonds [Member]
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale investments	2,253	4,097
Fair Value, Measurements, Recurring [Member] | Foreign Assets [Member]
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale investments		4,251
Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale investments	3,003	10,845
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Commercial Paper [Member]
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale investments	750	2,497
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Corporate Bonds [Member]
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale investments	$ 2,253	4,097
Fair Value, Measurements, Recurring [Member] | Level 2 [Member] | Foreign Assets [Member]
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale investments		$ 4,251

Fair Value Measurements - Addit

Fair Value Measurements - Additional Information (Detail)	3 Months Ended
	Mar. 31, 2017USD ($)
Fair Value Disclosures [Abstract]
Transfer of assets between level 1, level 2 or level 3	$ 0

Debt - Additional Information (

Debt - Additional Information (Detail)	1 Months Ended	3 Months Ended
	Mar. 31, 2017USD ($)Tranches	Mar. 31, 2017USD ($)	Dec. 31, 2016USD ($)	Dec. 31, 2013USD ($)
Debt Instrument [Line Items]
Description of deferred principal payment due		In February 2017, the Company entered into an amendment to the amended and restated loan and security agreement to allow principal payments due on February 1, 2017 and March 1, 2017 to be deferred until March 15, 2017. In March 2017, the principal payments were deferred again during renegotiations with Oxford.
Term Loans [Member]
Debt Instrument [Line Items]
Number of tranches | Tranches	3
Term Loans [Member] | Maximum [Member]
Debt Instrument [Line Items]
Amount borrowed under facility	$ 40,000,000	$ 40,000,000
First Term Loan [Member]
Debt Instrument [Line Items]
Amount borrowed under facility	13,500,000	13,500,000
Revolving Line of Credit [Member]
Debt Instrument [Line Items]
Line of credit facility, amount outstanding	8,000,000	8,000,000
Revolving Line of Credit [Member] | Maximum [Member]
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity	10,000,000	$ 10,000,000
Prior Credit Facility [Member]
Debt Instrument [Line Items]
Amount borrowed under facility			$ 20,000,000	$ 20,000,000
Fixed interest floor rate				9.40%
Maturity date of debt instrument		Dec. 1, 2018
New Credit Facility [Member]
Debt Instrument [Line Items]
Amount borrowed under facility	13,500,000	$ 13,500,000
Maturity date of debt instrument		Mar. 1, 2022
Long term debt, repayment of amount outstanding	20,000,000
Payment fee	$ 1,200,000
Credit facility final payment fee	4.95%
New Credit Facility [Member] | Maximum [Member] | Prior to First Anniversary [Member]
Debt Instrument [Line Items]
Credit facility prepayment fee	3.00%
New Credit Facility [Member] | Minimum [Member]
Debt Instrument [Line Items]
Credit facility secured by shares in foreign subsidiary	65.00%	65.00%
New Credit Facility [Member] | Minimum [Member] | Prior to First Anniversary [Member]
Debt Instrument [Line Items]
Credit facility prepayment fee	1.00%
New Credit Facility [Member] | Term Loans [Member]
Debt Instrument [Line Items]
Number of tranches | Tranches	3
New Credit Facility [Member] | Term Loans [Member] | Maximum [Member]
Debt Instrument [Line Items]
Amount borrowed under facility	$ 40,000,000	$ 40,000,000
New Credit Facility [Member] | First Term Loan [Member]
Debt Instrument [Line Items]
Amount borrowed under facility	13,500,000	13,500,000
New Credit Facility [Member] | Second Term Loan [Member] | Maximum [Member]
Debt Instrument [Line Items]
Amount borrowed under facility	10,000,000	10,000,000
New Credit Facility [Member] | Third Term Loan [Member] | Maximum [Member]
Debt Instrument [Line Items]
Amount borrowed under facility	16,500,000	16,500,000
New Credit Facility [Member] | Revolving Line of Credit [Member]
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity	10,000,000	10,000,000
Line of credit facility, amount outstanding	$ 8,000,000	$ 8,000,000
Debt instrument, description of floating rate terms		With respect to the Revolving Line of Credit, the floating per annum rate of interest is equal to the greater of (1) 4.95% and (2) the sum of (i) the greater of (A) 30-day U.S. LIBOR rate reported in The Wall Street Journal on the last business day of the month that immediately precedes the month in which the interest will accrue and (B) 0.77%, plus (ii) 4.18%.
Debt instrument, description of variable rate basis		30-day U.S. LIBOR
Debt instrument, interest rate	0.77%
Debt instrument, basis spread on interest rate	4.18%
New Credit Facility [Member] | Revolving Line of Credit [Member] | Maximum [Member]
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity	$ 10,000,000	$ 10,000,000
New Credit Facility [Member] | Revolving Line of Credit [Member] | Minimum [Member]
Debt Instrument [Line Items]
Debt instrument, floating per annum rate	4.95%	4.95%
New Credit Facility [Member] | Term Loans [Member]
Debt Instrument [Line Items]
Debt instrument, description of floating rate terms		Each Term Loan bears interest at a floating per annum rate equal to the greater of (1) 7.95% and (2) the sum of (i) the greater of (A) the 30-day U.S. LIBOR rate reported in The Wall Street Journal on the last business day of the month that immediately precedes the month in which the interest will accrue and (B) 0.77%, plus (ii) 7.18%.
Debt instrument, description of variable rate basis		30-day U.S. LIBOR
Debt instrument, interest rate	0.77%
Debt instrument, basis spread on interest rate	7.18%
Debt Instrument, frequency of periodic payment terms		The Company is required to make interest-only payments following the funding of each Term Loan through April 1, 2019 or, under certain circumstances, through April 1, 2020.
New Credit Facility [Member] | Term Loans [Member] | Minimum [Member]
Debt Instrument [Line Items]
Debt instrument, floating per annum rate	7.95%	7.95%

Debt - Schedule of Principal Pa

Debt - Schedule of Principal Payments under Term Loan (Detail) - New Credit Facility [Member] $ in Thousands	Mar. 31, 2017USD ($)
Debt Instrument [Line Items]
2,019	$ 3,375
2,020	4,500
2,021	4,500
2,022	1,125
Total principal payments	$ 13,500

Stockholders' Equity - Addition

Stockholders' Equity - Additional Information (Detail) - USD ($)	1 Months Ended	3 Months Ended		12 Months Ended
	Jan. 31, 2015	Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Preferred stock, shares authorized		10,000,000		10,000,000
Preferred stock, shares outstanding		0		0
Common stock, shares authorized		200,000,000		200,000,000
Common stock, shares outstanding		21,916,000		18,908,000
Common stock available for issuance		3,450,000		3,349,000
Stock-based compensation		$ 1,814,000	$ 1,205,000
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for issuance	200,000		232,976	197,014
Annual increase in shares available for grant		16,488	16,488
Increase in share reserve as percentage of shares of Common Stock outstanding on plan adoption date		1.00%
First offering date		Jan. 1, 2016
Stock issued during period shares		0	0	35,962
Maximum percentage of compensation employees can withheld		20.00%
Purchase price as a percentage of market price		85.00%
Employee Stock Purchase Plan, Plan Description		Under the ESPP, the Company has set two six-month offering periods during each calendar year, one beginning January 1 and ending on June 30, and the other beginning July 1 and ending on December 31, during which employees can choose to have up to 20% of their eligible compensation withheld to purchase less than 2,000 shares of the Company’s common stock during each offering period. The purchase price of the shares is 85% of the market price on the first or last trading day of the offering period, whichever is lower.
Maximum [Member] | Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation		$ 100,000	$ 100,000
Stock issued during period shares		2,000
2015 Incentive Award Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for issuance	1,346,570
Annual increase in shares available for grant	875,000	756,339	751,750
Annual percentage increase in shares available for grant	4.00%
Common stock available for issuance		959,294
Aggregate pre-tax intrinsic value of options exercised		$ 1,400,000	$ 300,000
Fair value of options vested		1,500,000	1,000,000
Total cash received upon the exercise of options		$ 700,000
2015 Incentive Award Plan [Member] | Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting term		4 years
Stock-based compensation		$ 200,000	0
2015 Incentive Award Plan [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total cash received upon the exercise of options			$ 100,000

Stockholders' Equity - Summary

Stockholders' Equity - Summary of Stock Option Activity and Related Information (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2017	Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Options outstanding, Beginning balance	3,349
Options Granted	427
Options Exercised	(123)
Options Forfeited	(203)
Options outstanding, Ending balance	3,450	3,349
Options Exercisable, Ending balance	1,528
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract]
Weighted Average Exercise Price, Beginning balance	$ 13.06
Weighted Average Exercise Price, Granted	16.96
Weighted Average Exercise Price, Exercised	5.46
Weighted Average Exercise Price, Forfeited	16.54
Weighted Average Exercise Price, Ending balance	13.61	$ 13.06
Weighted Average Exercise Price, Exercisable	$ 10.82
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Weighted Average Remaining Contractual Term	7 years 10 months 24 days	7 years 7 months 6 days
Weighted Average Remaining Contractual Term, Exercisable	6 years 9 months 18 days
Aggregate Intrinsic Value	$ 8,608	$ 21,863
Aggregate Intrinsic Value Exercisable	$ 7,102

Stockholders' Equity - Summar42

Stockholders' Equity - Summary of Restricted Stock Units Activity (Detail) - Restricted Stock Units [Member] - 2015 Incentive Award Plan [Member] shares in Thousands	3 Months Ended
	Mar. 31, 2017$ / sharesshares
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
RSUs outstanding, beginning of period	12
RSUs Granted	151
RSUs Released	(3)
RSUs Forfeited/expired	(8)
RSUs outstanding, end of period	152
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract]
Weighted average grant date fair value, Outstanding, beginning of period | $ / shares	$ 16.99
Weighted average grant date fair value, Outstanding, end of period | $ / shares	$ 17.80

Stock Based Compensation Expe43

Stock Based Compensation Expense - Summary of Stock-Based Compensation Expense in Condensed Consolidated Statement of Operations and Comprehensive Loss (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	$ 1,814	$ 1,205
Cost of Goods Sold [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	33	22
Selling and Marketing [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	619	448
Research and Development [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	221	124
General and Administrative [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	$ 941	$ 611

Stock Based Compensation Expe44

Stock Based Compensation Expense - Additional Information (Detail) $ in Millions	3 Months Ended
	Mar. 31, 2017USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested stock options awards	$ 14.5
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested other than stock options awards	$ 0.1
Remaining weighted-average vesting period for unrecognized stock-based compensation expense	3 months 18 days
Unvested Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Remaining weighted-average vesting period for unrecognized stock-based compensation expense	2 years 7 months 6 days
RSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested other than stock options awards	$ 2.5
Remaining weighted-average vesting period for unrecognized stock-based compensation expense	3 years 8 months 12 days

Stock Based Compensation Expe45

Stock Based Compensation Expense - Summary of Weighted Average Assumptions Used in Black-Scholes Model in Estimating Fair Value of Option Granted (Detail) - $ / shares	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected life in years	6 months	6 months
Risk-free interest rate	0.60%	0.50%
Expected dividend yield	0.00%	0.00%
Expected volatility	36.00%	54.00%
Weighted average fair value	$ 4.75	$ 5.15
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected life in years	6 years 3 months 18 days	6 years
Risk-free interest rate, minimum	2.10%	1.50%
Risk-free interest rate, maximum	2.20%	1.90%
Expected dividend yield	0.00%	0.00%
Expected volatility, minimum	52.00%	50.00%
Expected volatility, maximum	54.00%	51.00%
Weighted average fair value	$ 8.89	$ 8.22

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($)	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Income Tax Disclosure [Abstract]
Federal income tax benefit	$ 0	$ 0
State income tax benefit	0	0
Foreign income tax benefit	$ 0	$ 0

Earnings Per Share - Schedule o

Earnings Per Share - Schedule of Net Loss Per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Earnings Per Share [Abstract]
Net loss	$ (8,338)	$ (6,872)
Weighted average common stock outstanding	20,876	18,801
Net loss per share, basic and diluted	$ (0.40)	$ (0.37)

Earnings Per Share - Schedule48

Earnings Per Share - Schedule of Antidilutive Securities Outstanding Excluded from Computation of Earnings Per Share (Detail) - shares shares in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive potential common shares excluded from computation of diluted earning per share	3,668	3,008
Common Stock Warrants [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive potential common shares excluded from computation of diluted earning per share	38	38
Common Stock Options [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive potential common shares excluded from computation of diluted earning per share	3,450	2,939
Restricted Stock Units [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive potential common shares excluded from computation of diluted earning per share	152	12
Common Stock ESPP [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive potential common shares excluded from computation of diluted earning per share	28	19

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Detail) $ in Millions	Feb. 26, 2015	Jun. 30, 2014	Feb. 29, 2012	Mar. 31, 2017USD ($)Facilities	Mar. 31, 2016USD ($)
Commitments And Contingencies Disclosure [Abstract]
Number of leased facilities under operating lease agreement | Facilities				3
Operating leased facility, period		50 months	41 months
Operating leased facility, effective date		Jul. 1, 2014	Apr. 1, 2012
Operating leased facility, additional period	3 years
Operating leased facility, amendment description				On June 30, 2015, the Company entered into amendments to each lease agreement, among other things, to expand the space occupied by the Company at the property at which the Company’s corporate headquarters are located, and to extend the term of each lease agreement through June 2021, with an option to extend for an additional term through June 2024.
Total lease expense | $				$ 0.2	$ 0.1