Entellus Medical (ENTL) 10-Q 5 May 16 2016 Q1 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	3 Months Ended
	Mar. 31, 2016	Apr. 29, 2016
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Mar. 31, 2016
Document Fiscal Year Focus	2,016
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	Non-accelerated Filer
Entity Common Stock, Shares Outstanding		18,818,334

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets (Parenthetical) - $ / shares	Mar. 31, 2016	Dec. 31, 2015
Statement Of Financial Position [Abstract]
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	18,818,000	18,794,000
Common stock, shares outstanding	18,818,000	18,794,000

Condensed Consolidated Balance3

Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015	[1]
CURRENT ASSETS
Cash and cash equivalents	$ 23,766	$ 28,548
Short-term investments	38,034	38,210
Accrued interest income	112	247
Accounts receivable, net	10,263	10,440
Inventories	3,851	3,889
Prepaid expenses and other current assets	1,701	1,691
Total current assets	77,727	83,025
PROPERTY AND EQUIPMENT, NET	4,395	4,126
Other non-current assets	105	34
Total assets	82,227	87,185
CURRENT LIABILITIES
Accounts payable	2,604	2,208
Accrued expenses	7,110	6,995
Current portion of long-term debt	1,600
Total current liabilities	11,314	9,203
LONG-TERM LIABILITIES
Long-term debt, less current portion	18,238	19,824
Other non-current liabilities	641	562
Total liabilities	$ 30,193	$ 29,589
COMMITMENTS AND CONTINGENCIES (See Note M)
STOCKHOLDERS' EQUITY (see Note I)
Preferred stock, $0.001 par value per share: Authorized shares: 10,000 at March 31, 2016 and December 31, 2015 Issued and outstanding shares: none
Common stock, $0.001 par value per share: Authorized share: 200,000 at March 31, 2016 and December 31, 2015; Issued and outstanding shares: 18,818 and 18,794 at March 31, 2016 and December 31, 2015, respectively	$ 19	$ 19
Additional paid-in capital	180,925	179,673
Accumulated other comprehensive income (loss)	20	(38)
Accumulated deficit	(128,930)	(122,058)
Total stockholders' equity	52,034	57,596
Total liabilities and stockholders' equity	$ 82,227	$ 87,185
[1]	Amounts derived from audited financial statements of Entellus Medical, Inc. included in its Annual Report on Form 10-K for the year ended December 31, 2015.

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations and Comprehensive Loss - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Income Statement [Abstract]
Revenue	$ 16,902	$ 13,502
Cost of goods sold	4,000	2,949
Gross profit	12,902	10,553
Operating expenses
Selling and marketing	13,407	9,887
Research and development	1,912	1,300
General and administrative	3,949	2,816
Total operating expenses	19,268	14,003
Loss from operations	(6,366)	(3,450)
Other income (expense)
Interest income	70	21
Interest expense	(562)	(919)
Other non-operating expense	(14)
Total other expense, net	(506)	(898)
Net loss	(6,872)	(4,348)
Other comprehensive income (loss)
Unrealized gain on short term investments, net of tax	69	21
Foreign currency translation loss	(11)
Comprehensive loss	$ (6,814)	$ (4,327)
Net loss per share, basic and diluted	$ (0.37)	$ (0.35)
Weighted average common shares used to compute net loss per share, basic and diluted	18,801	12,542

Condensed Consolidated Stateme5

Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016		Mar. 31, 2015
Cash flows from operating activities:
Net loss	$ (6,872)		$ (4,348)
Adjustments to reconcile net loss to net cash used in operating activities:
Depreciation and amortization	349		198
Amortization of debt issuance costs	15		15
Amortization of premium on investments	79		51
Accretion of final payment fee on long-term debt	77		77
Deferred rent	3		1
Stock-based compensation	1,205		466
Changes in fair value of convertible preferred stock warrants			357
Changes in operating assets and liabilities:
Accrued interest income	135		(248)
Accounts receivables, net	164		322
Inventories	38		(157)
Prepaid expenses and other current assets	(10)		(321)
Other non-current assets	(71)		1,699
Accounts payable	396		(372)
Accrued expenses	115		593
Net cash used in operating activities	(4,377)		(1,667)
Cash flows from investing activities:
Purchase of property and equipment	(618)		(566)
Purchase of investments	(21,784)		(65,390)
Proceeds from maturities of short-term investments	21,950		2,750
Net cash used in investing activities	(452)		(63,206)
Cash flows from financing activities:
Proceeds from stock options exercised	47		169
Proceeds from initial public offering, net of issuance costs			80,953
Repurchase of common stock			(1)
Net cash provided by financing activities	47		81,121
Net (decrease) increase in cash and cash equivalents	(4,782)		16,248
Cash and cash equivalents - beginning of period	28,548	[1]	3,484
Cash and cash equivalents - end of period	23,766		19,732
Supplemental cash flow information:
Cash paid for interest	$ 470		$ 454
[1]	Amounts derived from audited financial statements of Entellus Medical, Inc. included in its Annual Report on Form 10-K for the year ended December 31, 2015.

Organization

Organization	3 Months Ended
	Mar. 31, 2016
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 the design, development and commercialization of products for the minimally invasive treatment of patients suffering from chronic sinusitis. The Company’s XprESS ™

Summary of Significant Accounti

Summary of Significant Accounting Policies	3 Months Ended
	Mar. 31, 2016
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, 2016 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, 2016 and 2015. 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, 2015 that has been filed with the SEC. Initial Public Offering In February 2015, the Company completed its initial public offering (“IPO”) by issuing 5,294 shares of common stock, at an offering price of $17.00 per share, for net proceeds of approximately $80,953 after deducting underwriting discounts, commissions and offering expenses payable by the Company. In connection with the IPO, the Company’s outstanding shares of convertible preferred stock were automatically converted into an aggregate of 11,404 shares of common stock, and the Company’s outstanding warrants to purchase shares of convertible preferred stock were automatically converted into warrants to purchase up to an aggregate of 38 shares of common stock, resulting in the reclassification of the related redeemable convertible preferred stock warrant liability of $648 to additional paid-in-capital. 1-for-4 Reverse Stock Split In connection with the IPO, the Company’s board of directors and stockholders approved a reverse stock split of the Company’s common stock on a 1-for-4 basis. The reverse stock split became effective on January 12, 2015. The par value of the common stock was not adjusted as a result of the reverse stock split. Adjustments corresponding to the reverse stock split were made to the ratio at which the convertible preferred stock converted into common stock immediately prior to the closing of the IPO. Accordingly, all share and per share amounts for all periods presented in these financial statements and notes thereto have been adjusted retroactively, where applicable, to reflect the reverse stock split and adjustment of the preferred stock’s conversion ratios. 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, 2016, 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, 2015. Recent Accounting Pronouncements In May 2014, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 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. The new guidance is effective for annual and interim periods beginning after December 15, 2017. The Company is in the process of evaluating the impact of the adoption of this standard. In April 2015, the FASB issued ASU 2015-03, Simplifying the Presentation of Debt Issuance, which changes the presentation of debt issuance costs in financial statements. Under ASU 2015-03, an entity presents such costs in the balance sheet as a direct deduction from the related debt liability rather than as an asset. Amortization of the costs is reported as interest expense. ASU 2015-03 is effective for fiscal years and interim periods within those fiscal years, beginning after December 15, 2015 . Early adoption is permitted for financial statements that have not been previously issued. A company should apply the new guidance on a retrospective basis, wherein the balance sheet of each individual period presented should be adjusted to reflect the period-specific effects of applying the new guidance. Upon transition, a company is required to comply with the applicable disclosures for a change in an accounting principle. The guidance only affects the presentation of debt issuance costs in the balance sheet and has no impact on results of operations. 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 is effective for interim and annual periods beginning after December 15, 2018, and early adoption is permitted. 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, and classification on the statement of cash flows. ASU 2016-09 is effective for annual periods beginning after December 15, 2016, and interim periods therein. Early application is permitted. The Company is currently evaluating the impact of this guidance on its consolidated financial statements.

Composition of Certain Financia

Composition of Certain Financial Statement Items	3 Months Ended
	Mar. 31, 2016
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, 2016 2015 Finished goods $ 1,353 $ 1,487 Work in process 902 388 Raw materials 1,596 2,014 Total $ 3,851 $ 3,889 Property and Equipment March 31, December 31, 2016 2015 Furniture and office equipment $ 563 $ 533 Computer hardware and software 2,349 2,187 Laboratory equipment 3,167 2,915 Tooling and molds 1,257 1,243 Leasehold improvements 583 583 $ 7,919 $ 7,461 Less accumulated depreciation and amortization (4,115 ) (3,766 ) Property and equipment in progress 591 431 Total $ 4,395 $ 4,126 Depreciation and amortization expense was $349 and $198 during the three months ended March 31, 2016 and 2015, respectively. Other Non-Current Assets March 31, December 31, 2016 2015 Security deposit on operating lease $ 34 $ 34 Deferred offering costs 71 — Total $ 105 $ 34 Accrued Expenses March 31, December 31, 2016 2015 Compensation and commissions payable $ 3,984 $ 3,898 Royalty payable 1,645 1,800 Other accrued expenses 1,481 1,297 Total $ 7,110 $ 6,995

Liquidity and Business Risks

Liquidity and Business Risks	3 Months Ended
	Mar. 31, 2016
Equity [Abstract]
Liquidity and Business Risks	NOTE D. LIQUIDITY AND BUSINESS RISKS As of March 31, 2016, the Company had cash, cash equivalents and short-term investments of $61,800 and an accumulated deficit of $128,930. In February 2015, the Company completed its IPO by issuing 5,294 shares of common stock at an offering price of $17.00 per share, for net proceeds of approximately $80,953, after deducting underwriting discounts and commissions and offering expenses. Prior to the 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 revenue will be sufficient to fund its operations through at least the next twelve months.

Short-Term Investments

Short-Term Investments	3 Months Ended
	Mar. 31, 2016
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 sheet as of March 31, 2016 and December 31, 2015. Unrealized Unrealized Gain in Losses in Accumulated Accumulated Other Other Amortized Comprehensive Comprehensive Estimated March 31, 2016 Cost Income (Loss) Income (Loss) Fair Value Commercial paper $ 13,446 $ 34 $ — $ 13,480 Corporate bonds 15,677 6 — 15,683 Foreign assets 8,858 13 — 8,871 Total available-for-sale securities $ 37,981 $ 53 $ — $ 38,034 Unrealized Unrealized Gain in Losses in Accumulated Accumulated Other Other Amortized Comprehensive Comprehensive Estimated December 31, 2015 Cost Income (Loss) Income (Loss) Fair Value Commercial paper $ 9,482 $ 10 $ — $ 9,492 Corporate bonds 19,605 — (19 ) 19,586 Government bonds 1,999 — — 1,999 Foreign assets 7,140 — (7 ) 7,133 Total available-for-sale securities $ 38,226 $ 10 $ (26 ) $ 38,210 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, 2016. The Company considered various factors which included 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, 2016 and December 31, 2015, 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, 2016
Fair Value Disclosures [Abstract]
Fair Value Measurements	NOTE F. FAIR VALUE MEASUREMENTS As of March 31, 2016 and as of December 31, 2015, 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, 2016 and December 31, 2015, respectively. March 31, 2016 Level 1 Level 2 Level 3 Total Commercial paper $ — $ 13,480 $ — $ 13,480 Corporate bonds — 15,683 — 15,683 Foreign assets — 8,871 — 8,871 Total $ — $ 38,034 $ — $ 38,034 December 31, 2015 Level 1 Level 2 Level 3 Total Commercial paper $ — $ 9,492 $ — $ 9,492 Corporate bonds — 19,586 — 19,586 Government bonds — 1,999 — 1,999 Foreign assets — 7,133 — 7,133 Total $ — $ 38,210 $ — $ 38,210 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, 2016. Convertible Preferred Stock Warranty Liability The following table sets forth a summary of the changes in the estimated fair value of the Company’s convertible preferred stock warrants, which represents financial instruments that were categorized as Level 3, according to the three-level fair value hierarchy. Three Months Ended March 31, 2016 2015 Beginning of the period $ — $ 291 Issued — — Exercised — — Expired — — Reclassified to equity (1) — (648 ) Change in fair value — 357 End of the period $ — $ — (1) In connection with the closing of the IPO in February 2015, warrants to purchase shares of convertible preferred stock were converted to warrants to purchase shares of common stock, resulting in the reclassification of the related convertible preferred stock warrant liability to additional paid-in-capital. The fair market value of the convertible preferred stock prior to the IPO was determined using the option pricing method and the probability weighted expected return method. The fair value of the convertible preferred stock warrant liability was determined using the Black-Scholes option pricing model with the following assumptions: Three Months Ended March 31, 2016 2015 Expected life in years N/A 7.5 Risk-free interest rate N/A 1.6 % Expected dividend yield N/A 0.0 % Expected volatility N/A 56 %

Debt

Debt	3 Months Ended
	Mar. 31, 2016
Debt Disclosure [Abstract]
Debt	NOTE G. DEBT In December 2013, we entered into an amended and restated credit facility (the “credit facility”) with Oxford Finance LLC. On March 30, 2015, we entered into an amendment to the credit facility, changing our obligation to deliver consolidated financial statements from monthly to quarterly, so long as we are required to make periodic filings with the Securities and Exchange Commission. On May 19, 2015, the Company entered into an amendment to the Company’s amended and restated loan and security agreement changing the Company’s obligations related to foreign subsidiaries. Under the credit facility, the Company could borrow up to a total of $25,000 in three tranches at a fixed rate of 9.40%. The first tranche of $15,000, including the refinance of $7,500 previously outstanding, was borrowed in December 2013. In connection with the funding of the first tranche, the Company paid a prorated final payment fee on the original credit facility of $143. The second tranche of up to $5,000 was available through December 31, 2014, of which $5,000 was borrowed during the three months ended December 31, 2014. The third tranche of up to $5,000 was available at any time through December 31, 2015, subject to certain six-month revenue milestones. The Company achieved the specified revenue milestones for the third tranche but elected not to borrow additional funds. The credit facility matures and all amounts borrowed thereunder are due on December 1, 2018. As a result of achieving certain funding and revenue milestones provided for in the credit facility in December 2015, the Company was permitted to extend the interest-only period to February 2017. After February 2017, the Company will make 24 monthly payment of principal and interest. In addition to the principal and interest payments, under the credit facility the Company is required to pay a final payment fee of 7.15% on all amounts outstanding, which is being accrued over the credit facility term and shall be due at the earlier of maturity or prepayment. If the Company repays the amounts borrowed under the credit facility prior to maturity, the Company will also be required to pay a prepayment fee equal to 0.75%, with respect to the principal amount that is prepaid. As of March 31, 2016 and December 31, 2015, the Company has borrowed and had outstanding $20,000 of debt under the credit facility. As of March 31, 2016 and as of December 31, 2015, the carrying amounts of debt approximates fair market. The fair value of the Company’s debt is considered a Level 3 measurement.

Convertible Preferred Stock

Convertible Preferred Stock	3 Months Ended
	Mar. 31, 2016
Temporary Equity Disclosure [Abstract]
Convertible Preferred Stock	NOTE H. CONVERTIBLE PREFERRED STOCK In connection with the IPO in February 2015, the 44,317 shares of convertible preferred stock were converted into 11,404 shares of common stock, resulting in the reclassification of the related redeemable convertible preferred stock of $91,554 to common stock and additional paid-in-capital.

Stockholders' Equity (Deficit)

Stockholders' Equity (Deficit)	3 Months Ended
	Mar. 31, 2016
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stockholders' Equity (Deficit)	NOTE I. STOCKHOLDERS’ EQUITY Preferred Stock The amended and restated certificate of incorporation, as amended in connection with the IPO, authorizes 10,000 shares of preferred stock. As of March 31, 2016, no preferred stock had been issued. Common Stock The amended and restated certificate of incorporation, as amended in connection with the IPO, authorizes 200,000 shares of common stock. 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. 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. 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 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 shares, (B) 4% of the outstanding shares of the Company’s common stock as of the last day of the immediately preceding fiscal year or (C) an amount determined by the Company’s Board of Directors. In accordance with this “evergreen” provision, the number of shares available under the 2015 plan was increased in the amount of 752 shares resulting in a total of 2,098 shares of common stock available. A summary of the Company’s stock option and restricted stock unit activity and related information is as follows: March 31, 2016 Weighted average Aggregate Weighted remaining intrinsic average contractual value Options exercise price term ($000) Outstanding, beginning of period 2,583 $ 11.79 8.5 years $ 16,377 Granted 393 16.74 Exercised (24 ) 1.93 Cancelled — — Forfeited (13 ) 16.52 Outstanding, end of period 2,939 $ 12.51 8.5 years $ 19,128 Exercisable 951 $ 7.41 7.2 years $ 10,708 The aggregate pre-tax intrinsic value of options exercised was $342 and $1,530 for the three months ended March 31, 2016 and 2015, 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, 2016. The total cash received upon the exercise of options was $47 and $169 during the three months ended March 31, 2016 and 2015, respectively. During the three months ended March 31, 2016, the Company issued 12 restricted stock units (“RSU’s”) at a weighted average fair value of $16.99. 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, we have 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 compensation withheld to purchase up to 2 shares of our 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 shares of common stock were initially reserved for issuance under the ESPP. In addition, the number of shares 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 quarter of 2016, in accordance with the “evergreen” provision, the number of shares available for grant under the ESPP increased in the amount of 17 shares, resulting in a total of 217 shares of common stock reserved for issuance under the ESPP. During the three months ended March 31, 2016 the Company did not issue shares of its common stock to participants under the 2015 ESPP. However, the Company recognized $49 in stock-based compensation related to the ESPP.

Stock Based Compensation Expens

Stock Based Compensation Expense	3 Months Ended
	Mar. 31, 2016
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Stock Based Compensation Expense	NOTE J. 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, 2016 and 2015, as follows: Three Months Ended March 31, 2016 2015 Cost of goods sold $ 22 $ 10 Selling and marketing 124 87 Research and development 448 44 General and administrative 611 325 Total $ 1,205 $ 466 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 the Company’s limited operating history and a lack of company-specific historical and implied volatility data, the Company has based its estimate of expected volatility on the historical volatility of a group of similar companies that are publicly traded. The historical volatility data was computed using the daily closing prices for the selected companies’ shares during the equivalent period of the calculated expected term of the share-based payments. The Company will continue to analyze the historical stock price volatility and expected term assumptions as more historical data for the Company’s common stock becomes available. The risk-free rate assumption is based on the U.S. Treasury instruments with maturities similar to the expected term of the Company’s stock options. The expected dividend assumption is based on the Company’s history of not paying dividends and its expectation that it will not declare dividends for the foreseeable future. As stock-based compensation expense recognized in the financial statements is based on awards ultimately expected to vest, it has been reduced for estimated forfeitures. Forfeitures are estimated at the time of grant and revised, if necessary, in subsequent periods if actual forfeitures differ from estimates. Forfeitures are estimated based on estimated future employee turnover and historical experience. The fair value of the options granted to employees or directors during the three months ended March 31, 2016 and 2015 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, 2016 2015 Expected life in years 6.0 5.9 Risk-free interest rate 1.8 % 1.6 % Expected dividend yield 0 % 0 % Expected volatility 50 % 56 % Weighted average fair value $ 8.22 $ 11.30 The fair value of the ESPP options granted to employees during the three months ended March 31, 2016 and 2015 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, 2016 2015 Expected life in years 0.5 N/A Risk-free interest rate 0.5 % N/A Expected dividend yield 0 % N/A Expected volatility 1 % N/A Weighted average fair value $ 16.99 $ N/A

Income Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2016
Income Tax Disclosure [Abstract]
Income Taxes	NOTE K. INCOME TAXES We did not record a federal or state income tax benefit for our losses for the three months ended March 31, 2016 and 2015 due to our conclusion that full valuation allowance is required against our deferred tax assets.

Earnings Per Share

Earnings Per Share	3 Months Ended
	Mar. 31, 2016
Earnings Per Share [Abstract]
Earnings Per Share	NOTE L. 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 stock options, warrants and ESPP shares 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, 2016 2015 Net loss $ (6,872 ) $ (4,348 ) Weighted average common stock outstanding 18,801 12,542 Net loss per share, basic and diluted $ (0.37 ) $ (0.35 ) 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, 2016 2015 Common stock warrants 38 38 Common stock options 2,939 2,011 Restricted stock units 12 — Common stock ESPP 19 — Total 3,008 2,049

Commitments and Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2016
Commitments And Contingencies Disclosure [Abstract]
Commitments and Contingencies	NOTE M. COMMITMENTS AND CONTINGENCIES Operating Leases As of March 31, 2016, the Company has two leased facilities under operating lease agreements. The Company entered into a 41-month lease in February 2012, effective April 1, 2012, for its 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. The 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 $136 and $90 for the three months ended March 31, 2016 and 2015, respectively.

Summary of Significant Accoun19

Summary of Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2016
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, 2016 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, 2016 and 2015. 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, 2015 that has been filed with the SEC.
Initial Public Offering	Initial Public Offering In February 2015, the Company completed its initial public offering (“IPO”) by issuing 5,294 shares of common stock, at an offering price of $17.00 per share, for net proceeds of approximately $80,953 after deducting underwriting discounts, commissions and offering expenses payable by the Company. In connection with the IPO, the Company’s outstanding shares of convertible preferred stock were automatically converted into an aggregate of 11,404 shares of common stock, and the Company’s outstanding warrants to purchase shares of convertible preferred stock were automatically converted into warrants to purchase up to an aggregate of 38 shares of common stock, resulting in the reclassification of the related redeemable convertible preferred stock warrant liability of $648 to additional paid-in-capital.
1-for-4 Reverse Stock Split	1-for-4 Reverse Stock Split In connection with the IPO, the Company’s board of directors and stockholders approved a reverse stock split of the Company’s common stock on a 1-for-4 basis. The reverse stock split became effective on January 12, 2015. The par value of the common stock was not adjusted as a result of the reverse stock split. Adjustments corresponding to the reverse stock split were made to the ratio at which the convertible preferred stock converted into common stock immediately prior to the closing of the IPO. Accordingly, all share and per share amounts for all periods presented in these financial statements and notes thereto have been adjusted retroactively, where applicable, to reflect the reverse stock split and adjustment of the preferred stock’s conversion ratios.
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 Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) No. 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. The new guidance is effective for annual and interim periods beginning after December 15, 2017. The Company is in the process of evaluating the impact of the adoption of this standard. In April 2015, the FASB issued ASU 2015-03, Simplifying the Presentation of Debt Issuance, which changes the presentation of debt issuance costs in financial statements. Under ASU 2015-03, an entity presents such costs in the balance sheet as a direct deduction from the related debt liability rather than as an asset. Amortization of the costs is reported as interest expense. ASU 2015-03 is effective for fiscal years and interim periods within those fiscal years, beginning after December 15, 2015 . Early adoption is permitted for financial statements that have not been previously issued. A company should apply the new guidance on a retrospective basis, wherein the balance sheet of each individual period presented should be adjusted to reflect the period-specific effects of applying the new guidance. Upon transition, a company is required to comply with the applicable disclosures for a change in an accounting principle. The guidance only affects the presentation of debt issuance costs in the balance sheet and has no impact on results of operations. 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 is effective for interim and annual periods beginning after December 15, 2018, and early adoption is permitted. 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, and classification on the statement of cash flows. ASU 2016-09 is effective for annual periods beginning after December 15, 2016, and interim periods therein. Early application is permitted. The Company is currently evaluating the impact of this guidance on its consolidated financial statements.

Composition of Certain Financ20

Composition of Certain Financial Statement Items (Tables)	3 Months Ended
	Mar. 31, 2016
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Schedule of Inventories	Inventories March 31, December 31, 2016 2015 Finished goods $ 1,353 $ 1,487 Work in process 902 388 Raw materials 1,596 2,014 Total $ 3,851 $ 3,889
Schedule of Property and Equipment	Property and Equipment March 31, December 31, 2016 2015 Furniture and office equipment $ 563 $ 533 Computer hardware and software 2,349 2,187 Laboratory equipment 3,167 2,915 Tooling and molds 1,257 1,243 Leasehold improvements 583 583 $ 7,919 $ 7,461 Less accumulated depreciation and amortization (4,115 ) (3,766 ) Property and equipment in progress 591 431 Total $ 4,395 $ 4,126
Schedule of Other Non-Current Assets	Other Non-Current Assets March 31, December 31, 2016 2015 Security deposit on operating lease $ 34 $ 34 Deferred offering costs 71 — Total $ 105 $ 34
Schedule of Accrued Expenses	Accrued Expenses March 31, December 31, 2016 2015 Compensation and commissions payable $ 3,984 $ 3,898 Royalty payable 1,645 1,800 Other accrued expenses 1,481 1,297 Total $ 7,110 $ 6,995

Short-Term Investments (Tables)

Short-Term Investments (Tables)	3 Months Ended
	Mar. 31, 2016
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 sheet as of March 31, 2016 and December 31, 2015. Unrealized Unrealized Gain in Losses in Accumulated Accumulated Other Other Amortized Comprehensive Comprehensive Estimated March 31, 2016 Cost Income (Loss) Income (Loss) Fair Value Commercial paper $ 13,446 $ 34 $ — $ 13,480 Corporate bonds 15,677 6 — 15,683 Foreign assets 8,858 13 — 8,871 Total available-for-sale securities $ 37,981 $ 53 $ — $ 38,034 Unrealized Unrealized Gain in Losses in Accumulated Accumulated Other Other Amortized Comprehensive Comprehensive Estimated December 31, 2015 Cost Income (Loss) Income (Loss) Fair Value Commercial paper $ 9,482 $ 10 $ — $ 9,492 Corporate bonds 19,605 — (19 ) 19,586 Government bonds 1,999 — — 1,999 Foreign assets 7,140 — (7 ) 7,133 Total available-for-sale securities $ 38,226 $ 10 $ (26 ) $ 38,210

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	3 Months Ended
	Mar. 31, 2016
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, 2016 and December 31, 2015, respectively. March 31, 2016 Level 1 Level 2 Level 3 Total Commercial paper $ — $ 13,480 $ — $ 13,480 Corporate bonds — 15,683 — 15,683 Foreign assets — 8,871 — 8,871 Total $ — $ 38,034 $ — $ 38,034 December 31, 2015 Level 1 Level 2 Level 3 Total Commercial paper $ — $ 9,492 $ — $ 9,492 Corporate bonds — 19,586 — 19,586 Government bonds — 1,999 — 1,999 Foreign assets — 7,133 — 7,133 Total $ — $ 38,210 $ — $ 38,210
Summary of Changes in Estimated Fair Value of Company's Convertible Preferred Stock Warrants	The following table sets forth a summary of the changes in the estimated fair value of the Company’s convertible preferred stock warrants, which represents financial instruments that were categorized as Level 3, according to the three-level fair value hierarchy. Three Months Ended March 31, 2016 2015 Beginning of the period $ — $ 291 Issued — — Exercised — — Expired — — Reclassified to equity (1) — (648 ) Change in fair value — 357 End of the period $ — $ — (1) In connection with the closing of the IPO in February 2015, warrants to purchase shares of convertible preferred stock were converted to warrants to purchase shares of common stock, resulting in the reclassification of the related convertible preferred stock warrant liability to additional paid-in-capital.
Summary of Fair Value of Convertible Preferred Stock Warrant Liability	The fair market value of the convertible preferred stock prior to the IPO was determined using the option pricing method and the probability weighted expected return method. The fair value of the convertible preferred stock warrant liability was determined using the Black-Scholes option pricing model with the following assumptions: Three Months Ended March 31, 2016 2015 Expected life in years N/A 7.5 Risk-free interest rate N/A 1.6 % Expected dividend yield N/A 0.0 % Expected volatility N/A 56 %

Stockholders' Equity (Deficit)

Stockholders' Equity (Deficit) (Tables)	3 Months Ended
	Mar. 31, 2016
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Summary of Stock Option Activity and Related Information	A summary of the Company’s stock option and restricted stock unit activity and related information is as follows: March 31, 2016 Weighted average Aggregate Weighted remaining intrinsic average contractual value Options exercise price term ($000) Outstanding, beginning of period 2,583 $ 11.79 8.5 years $ 16,377 Granted 393 16.74 Exercised (24 ) 1.93 Cancelled — — Forfeited (13 ) 16.52 Outstanding, end of period 2,939 $ 12.51 8.5 years $ 19,128 Exercisable 951 $ 7.41 7.2 years $ 10,708

Stock Based Compensation Expe24

Stock Based Compensation Expense (Tables)	3 Months Ended
	Mar. 31, 2016
Summary of Stock-based Compensation Expense in Condensed 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, 2016 and 2015, as follows: Three Months Ended March 31, 2016 2015 Cost of goods sold $ 22 $ 10 Selling and marketing 124 87 Research and development 448 44 General and administrative 611 325 Total $ 1,205 $ 466
Employee Stock Purchase Plan [Member]
Summary of Weighted Average Assumptions Used in Black-Scholes Model in Estimating Fair Value of Option Granted	The fair value of the ESPP options granted to employees during the three months ended March 31, 2016 and 2015 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, 2016 2015 Expected life in years 0.5 N/A Risk-free interest rate 0.5 % N/A Expected dividend yield 0 % N/A Expected volatility 1 % N/A Weighted average fair value $ 16.99 $ N/A
Employee Stock Option [Member]
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, 2016 and 2015 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, 2016 2015 Expected life in years 6.0 5.9 Risk-free interest rate 1.8 % 1.6 % Expected dividend yield 0 % 0 % Expected volatility 50 % 56 % Weighted average fair value $ 8.22 $ 11.30

Earnings Per Share (Tables)

Earnings Per Share (Tables)	3 Months Ended
	Mar. 31, 2016
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, 2016 2015 Net loss $ (6,872 ) $ (4,348 ) Weighted average common stock outstanding 18,801 12,542 Net loss per share, basic and diluted $ (0.37 ) $ (0.35 )
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, 2016 2015 Common stock warrants 38 38 Common stock options 2,939 2,011 Restricted stock units 12 — Common stock ESPP 19 — Total 3,008 2,049

Summary of Significant Accoun26

Summary of Significant Accounting Policies - Additional Information (Detail) $ / shares in Units, shares in Thousands, $ in Thousands	Jan. 12, 2015	Feb. 28, 2015USD ($)$ / sharesshares	Mar. 31, 2016USD ($)	Mar. 31, 2015USD ($)	Dec. 31, 2015USD ($)
Accounting Policies [Line Items]
Proceeds from initial public offering, net of issuance costs				$ 80,953
Reverse stock split conversion ratio	0.25
Debt Issuance Costs			$ 161		$ 176
Initial Public Offering [Member]
Accounting Policies [Line Items]
Common stock, shares issued | shares		5,294
Common stock offering price per share | $ / shares		$ 17
Proceeds from initial public offering, net of issuance costs		$ 80,953
Number of common stock converted from preferred stock | shares		11,404
Shares purchasable upon conversion of preferred stock | shares		38
Preferred stock warrant liability reclassified		$ 648

Composition of Certain Financ27

Composition of Certain Financial Statement Items - Schedule of Inventories (Detail) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Inventory Disclosure [Abstract]
Finished goods	$ 1,353	$ 1,487
Work in process	902	388
Raw materials	1,596	2,014
Total	$ 3,851	$ 3,889	[1]
[1]	Amounts derived from audited financial statements of Entellus Medical, Inc. included in its Annual Report on Form 10-K for the year ended December 31, 2015.

Composition of Certain Financ28

Composition of Certain Financial Statement Items - Schedule of Property and Equipment (Detail) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Property, Plant and Equipment [Line Items]
Property plant and equipment, Gross	$ 7,919	$ 7,461
Less accumulated depreciation and amortization	(4,115)	(3,766)
Property and equipment in progress	591	431
Total	4,395	4,126	[1]
Furniture and Office Equipment [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment, Gross	563	533
Computer Hardware and Software [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment, Gross	2,349	2,187
Laboratory Equipment [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment, Gross	3,167	2,915
Tooling and Molds [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment, Gross	1,257	1,243
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property plant and equipment, Gross	$ 583	$ 583
[1]	Amounts derived from audited financial statements of Entellus Medical, Inc. included in its Annual Report on Form 10-K for the year ended December 31, 2015.

Composition of Certain Financ29

Composition of Certain Financial Statement Items - Additional Information (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Property Plant And Equipment [Abstract]
Depreciation and amortization	$ 349	$ 198

Composition of Certain Financ30

Composition of Certain Financial Statement Items - Schedule of Other Non-Current Assets (Detail) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Assets Noncurrent [Abstract]
Security deposit on operating lease	$ 34	$ 34
Deferred offering costs	71
Other non-current assets, Total	$ 105	$ 34	[1]
[1]	Amounts derived from audited financial statements of Entellus Medical, Inc. included in its Annual Report on Form 10-K for the year ended December 31, 2015.

Composition of Certain Financ31

Composition of Certain Financial Statement Items - Schedule of Accrued Expenses (Detail) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Payables And Accruals [Abstract]
Compensation and commissions payable	$ 3,984	$ 3,898
Royalty payable	1,645	1,800
Other accrued expenses	1,481	1,297
Accrued expenses, Total	$ 7,110	$ 6,995	[1]
[1]	Amounts derived from audited financial statements of Entellus Medical, Inc. included in its Annual Report on Form 10-K for the year ended December 31, 2015.

Liquidity and Business Risks -

Liquidity and Business Risks - Additional Information (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	1 Months Ended	3 Months Ended
	Feb. 28, 2015	Mar. 31, 2015	Mar. 31, 2016	Dec. 31, 2015	[1]
Subsidiary, Sale of Stock [Line Items]
Cash, cash equivalents and short-term investments			$ 61,800
Accumulated deficit			$ 128,930	$ 122,058
Proceeds from initial public offering, net of issuance costs		$ 80,953
Initial Public Offering [Member]
Subsidiary, Sale of Stock [Line Items]
Common stock, shares issued	5,294
Common stock offering price per share	$ 17
Proceeds from initial public offering, net of issuance costs	$ 80,953
[1]	Amounts derived from audited financial statements of Entellus Medical, Inc. included in its Annual Report on Form 10-K for the year ended December 31, 2015.

Short-term Investments - Summar

Short-term Investments - Summary of Investments by Type of Instrument (Detail) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	$ 37,981	$ 38,226
Unrealized Gain in Accumulated Other Comprehensive Income	53	10
Unrealized Losses in Accumulated Other Comprehensive Income		(26)
Estimated Fair Value	38,034	38,210
Short-term Investments [Member] | Commercial Paper [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	13,446	9,482
Unrealized Gain in Accumulated Other Comprehensive Income	34	10
Estimated Fair Value	13,480	9,492
Short-term Investments [Member] | Corporate Bonds [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	15,677	19,605
Unrealized Gain in Accumulated Other Comprehensive Income	6
Unrealized Losses in Accumulated Other Comprehensive Income		(19)
Estimated Fair Value	15,683	19,586
Short-term Investments [Member] | Foreign Assets [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	8,858	7,140
Unrealized Gain in Accumulated Other Comprehensive Income	13
Unrealized Losses in Accumulated Other Comprehensive Income		(7)
Estimated Fair Value	$ 8,871	7,133
Short-term Investments [Member] | Government Bonds [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost		1,999
Estimated Fair Value		$ 1,999

Short-term Investments - Additi

Short-term Investments - Additional Information (Detail)	3 Months Ended
	Mar. 31, 2016USD ($)
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, 2016	Dec. 31, 2015	Mar. 31, 2015
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale investments	$ 38,034	$ 38,210
Fair Value, Measurements, Recurring [Member]
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale investments	38,034		$ 38,210
Fair Value, Measurements, Recurring [Member] | Level 2 [Member]
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale investments	38,034		38,210
Fair Value, Measurements, Recurring [Member] | Commercial Paper [Member]
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale investments	13,480		9,492
Fair Value, Measurements, Recurring [Member] | Commercial Paper [Member] | Level 2 [Member]
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale investments	13,480		9,492
Fair Value, Measurements, Recurring [Member] | Corporate Bonds [Member]
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale investments	15,683		19,586
Fair Value, Measurements, Recurring [Member] | Corporate Bonds [Member] | Level 2 [Member]
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale investments	15,683		19,586
Fair Value, Measurements, Recurring [Member] | Foreign Assets [Member]
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale investments	8,871		7,133
Fair Value, Measurements, Recurring [Member] | Foreign Assets [Member] | Level 2 [Member]
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale investments	$ 8,871		7,133
Fair Value, Measurements, Recurring [Member] | Government Bonds [Member]
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale investments			1,999
Fair Value, Measurements, Recurring [Member] | Government Bonds [Member] | Level 2 [Member]
Schedule Of Available For Sale Securities [Line Items]
Available-for-sale investments			$ 1,999

Fair Value Measurements - Addit

Fair Value Measurements - Additional Information (Detail)	3 Months Ended
	Mar. 31, 2016USD ($)
Fair Value Disclosures [Abstract]
Transfer of assets between level 1, level 2 or level 3	$ 0

Fair Value Measurements - Sum37

Fair Value Measurements - Summary of Changes in Estimated Fair Value of Company's Convertible Preferred Stock Warrants (Detail) - Convertible Preferred Stock Warrants [Member] $ in Thousands	3 Months Ended
	Mar. 31, 2015USD ($)
Class of Warrant or Right [Line Items]
Beginning of the period	$ 291
Reclassified to equity	(648)
Change in fair value	$ 357

Fair Value Measurements - Sum38

Fair Value Measurements - Summary of Fair Value of Convertible Preferred Stock Warrant Liability (Detail)	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Abstract]
Expected life in years	0 years	7 years 6 months
Risk-free interest rate		1.60%
Expected dividend yield		0.00%
Expected volatility		56.00%

Debt - Additional Information (

Debt - Additional Information (Detail) - Credit Facility [Member]	May. 19, 2015USD ($)Tranches	Dec. 31, 2013USD ($)	Mar. 31, 2016USD ($)	Dec. 31, 2015USD ($)	Dec. 31, 2014USD ($)
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity	$ 25,000,000
Line of credit facility, amount outstanding			$ 20,000,000	$ 20,000,000
Fixed interest floor rate	9.40%
Number of tranches | Tranches	3
Maturity date of debt instrument			Dec. 1, 2018
Credit facility interest payment period			24 months
Credit facility final payment fee			7.15%
First Tranche [Member]
Debt Instrument [Line Items]
Line of credit facility, amount outstanding		$ 15,000,000
Payment fee		143,000
Second Tranche [Member]
Debt Instrument [Line Items]
Line of credit facility, amount outstanding					$ 5,000,000
Third Tranche [Member]
Debt Instrument [Line Items]
Line of credit facility, maximum borrowing capacity				$ 5,000,000
Prior to First Anniversary [Member]
Debt Instrument [Line Items]
Credit facility prepayment fee			0.75%
Scenario, Previously Reported [Member] | First Tranche [Member]
Debt Instrument [Line Items]
Line of credit facility, amount outstanding		$ 7,500,000
Maximum [Member] | Second Tranche [Member]
Debt Instrument [Line Items]
Line of credit facility, amount outstanding					$ 5,000,000

Convertible Preferred Stock - A

Convertible Preferred Stock - Additional Information (Detail) - USD ($) shares in Thousands, $ in Thousands	1 Months Ended	3 Months Ended
	Feb. 28, 2015	Mar. 31, 2016
Temporary Equity [Line Items]
Preferred stock, conversion basis		In connection with the IPO in February 2015, the 44,317 shares of convertible preferred stock were converted into 11,404 shares of common stock, resulting in the reclassification of the related redeemable convertible preferred stock of $91,554 to common stock and additional paid-in-capital.
Number of preferred stock converted to common stock	44,317
Convertible preferred stock	$ 91,554
Initial Public Offering [Member]
Temporary Equity [Line Items]
Number of common stock converted from preferred stock	11,404

Stockholders' Equity (Deficit41

Stockholders' Equity (Deficit) - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	3 Months Ended
	Jan. 31, 2015	Mar. 31, 2016	Mar. 31, 2015	Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Preferred stock, shares authorized		10,000,000		10,000,000
Preferred stock, shares Issued		0		0
Common stock, shares authorized		200,000,000		200,000,000
Stock-based compensation		$ 1,205	$ 466
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for issuance		200,000
Weighted average fair value		$ 16.99
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
Stock-based compensation		$ 49
Shares of common stocks available for purchase by employee		2,000
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, we have 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 compensation withheld to purchase up to 2 shares of our 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.
Employee Stock Purchase Plan [Member] | Maximum [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Annual increase in shares available for grant		17,000
2015 Incentive Award Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock reserved for issuance	1,346,000	2,098,000
Annual increase in shares available for grant	875,000	752,000
Annual percentage increase in shares available for grant	4.00%
Aggregate pre-tax intrinsic value of options exercised		$ 342	1,530
Total cash received upon the exercise of options		$ 47	$ 169
2015 Incentive Award Plan [Member] | Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted shares issued		12,000
Weighted average fair value		$ 16.99

Stockholders' Equity (Deficit42

Stockholders' Equity (Deficit) - 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, 2016	Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Options outstanding, Beginning balance	2,583
Options Granted	393
Options Exercised	(24)
Options Forfeited	(13)
Options outstanding, Ending balance	2,939	2,583
Options Exercisable, Ending balance	951
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract]
Weighted Average Exercise Price, Beginning balance	$ 11.79
Weighted Average Exercise Price, Granted	16.74
Weighted Average Exercise Price, Exercised	1.93
Weighted Average Exercise Price, Forfeited	16.52
Weighted Average Exercise Price, Ending balance	12.51	$ 11.79
Weighted Average Exercise Price, Exercisable	$ 7.41
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]
Weighted Average Remaining Contractual Term	8 years 6 months	8 years 6 months
Weighted Average Remaining Contractual Term, Exercisable	7 years 2 months 12 days
Aggregate Intrinsic Value	$ 19,128	$ 16,377
Aggregate Intrinsic Value Exercisable	$ 10,708

Stock Based Compensation Expe43

Stock Based Compensation Expense - Summary of Stock-Based Compensation Expense in Condensed Statement of Operations and Comprehensive Loss (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	$ 1,205	$ 466
Cost of Goods Sold [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	22	10
Selling and Marketing [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	124	87
Research and Development [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	448	44
General and Administrative [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]
Stock-based compensation expense	$ 611	$ 325

Stock Based Compensation Expe44

Stock Based Compensation Expense - Additional Information (Detail) $ in Thousands	3 Months Ended
	Mar. 31, 2016USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested employee stock-based payment award	$ 15,253
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average period for unearned stock-based compensation cost	3 years

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, 2016	Mar. 31, 2015
Employee Stock Purchase Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected life in years	6 months	0 years
Risk-free interest rate	0.50%
Expected dividend yield	0.00%
Expected volatility	1.00%
Weighted average fair value	$ 16.99
Employee Stock Option [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected life in years	6 years	5 years 10 months 24 days
Risk-free interest rate	1.80%	1.60%
Expected dividend yield	0.00%	0.00%
Expected volatility	50.00%	56.00%
Weighted average fair value	$ 8.22	$ 11.30

Income Taxes - Additional Infor

Income Taxes - Additional Information (Detail) - USD ($)	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Income Tax Disclosure [Abstract]
Federal income tax benefit	$ 0	$ 0
State 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, 2016	Mar. 31, 2015
Earnings Per Share [Abstract]
Net loss	$ (6,872)	$ (4,348)
Weighted average common stock outstanding	18,801	12,542
Net loss per share, basic and diluted	$ (0.37)	$ (0.35)

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, 2016	Mar. 31, 2015
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive potential common shares excluded from computation of diluted earning per share	3,008	2,049
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	2,939	2,011
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	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	19

Commitments and Contingencies -

Commitments and Contingencies - Additional Information (Detail) $ in Thousands	Feb. 26, 2015	Jun. 30, 2014	Feb. 29, 2012	Mar. 31, 2016USD ($)Facilities	Mar. 31, 2015USD ($)
Commitments And Contingencies Disclosure [Abstract]
Number of leased facilities under operating lease agreement | Facilities				2
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 | $				$ 136	$ 90