Aerie Pharmaceuticals (AERI) 10-Q 9 Nov 17 2017 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2017	Nov. 02, 2017
Document And Entity Information [Abstract]
Document Type	10-Q
Amendment Flag	false
Document Period End Date	Sep. 30, 2017
Document Fiscal Year Focus	2,017
Document Fiscal Period Focus	Q3
Trading Symbol	AERI
Entity Registrant Name	AERIE PHARMACEUTICALS INC
Entity CIK	1,337,553
Current Fiscal Year End Date	--12-31
Entity Filer Category	Accelerated Filer
Entity Common Stock, Shares Outstanding (in shares)		36,704,726

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets (Unaudited) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Current assets
Cash and cash equivalents	$ 194,078	$ 197,945
Short-term investments	87,256	35,717
Prepaid expenses and other current assets	2,065	4,028
Total current assets	283,399	237,690
Long-term investments	901	0
Property, plant and equipment, net	19,246	7,857
Other assets	2,656	2,707
Total assets	306,202	248,254
Current liabilities
Accounts payable and other current liabilities	18,045	18,820
Interest payable	551	551
Total current liabilities	18,596	19,371
Convertible notes, net	123,769	123,539
Other non-current liabilities	4,569	0
Total liabilities	146,934	142,910
Commitments and contingencies (Note 11)
Stockholders’ equity
Preferred stock, $0.001 par value; 15,000,000 shares authorized as of September 30, 2017 and December 31, 2016; None issued and outstanding	0	0
Common stock, $0.001 par value; 150,000,000 shares authorized as of September 30, 2017 and December 31, 2016; 36,426,830 and 33,458,607 shares issued and outstanding as of September 30, 2017 and December 31, 2016, respectively	36	33
Additional paid-in capital	562,545	422,002
Accumulated other comprehensive loss	(98)	(68)
Accumulated deficit	(403,215)	(316,623)
Total stockholders’ equity	159,268	105,344
Total liabilities and stockholders’ equity	$ 306,202	$ 248,254

Condensed Consolidated Balance3

Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) - $ / shares	Sep. 30, 2017	Dec. 31, 2016
Statement of Financial Position [Abstract]
Preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized (in shares)	15,000,000	15,000,000
Preferred stock, issued (in shares)	0	0
Preferred stock, outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	150,000,000	150,000,000
Common stock, shares issued (in shares)	36,426,830	33,458,607
Common stock, shares outstanding (in shares)	36,426,830	33,458,607

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations and Comprehensive Loss (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Operating expenses
Selling, general and administrative	$ 19,774	$ 10,627	$ 51,402	$ 29,814
Research and development	12,408	12,688	33,977	38,301
Total operating expenses	32,182	23,315	85,379	68,115
Loss from operations	(32,182)	(23,315)	(85,379)	(68,115)
Other income (expense), net	(141)	(460)	(1,071)	(1,490)
Net loss before income taxes	(32,323)	(23,775)	(86,450)	(69,605)
Income tax expense	49	39	142	132
Net loss	$ (32,372)	$ (23,814)	$ (86,592)	$ (69,737)
Net loss per share attributable to common stockholders—basic and diluted (in dollars per share)	$ (0.89)	$ (0.81)	$ (2.48)	$ (2.52)
Weighted average number of common shares outstanding—basic and diluted (in shares)	36,210,329	29,380,453	34,932,551	27,632,090
Net loss	$ (32,372)	$ (23,814)	$ (86,592)	$ (69,737)
Unrealized (loss) gain on available-for-sale investments	(17)	(3)	(30)	166
Comprehensive loss	$ (32,389)	$ (23,817)	$ (86,622)	$ (69,571)

Condensed Consolidated Stateme5

Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016
Cash flows from operating activities
Net loss	$ (86,592)	$ (69,737)
Adjustments to reconcile net loss to net cash used in operating activities
Depreciation	916	702
Amortization of deferred financing costs and debt discount	230	227
Amortization and accretion of premium or discount on available-for-sale investments, net	52	403
Stock-based compensation	18,072	11,514
Unrealized foreign exchange loss	522	0
Changes in operating assets and liabilities
Prepaid, current and other assets	1,718	(916)
Accounts payable and other current liabilities	(1,981)	(3,187)
Net cash used in operating activities	(67,063)	(60,994)
Cash flows from investing activities
Purchase of available-for-sale investments	(101,217)	(19,948)
Proceeds from sales and maturities of investments	48,696	35,355
Purchase of property, plant and equipment	(7,073)	(1,392)
Net cash (used in) provided by investing activities	(59,594)	14,015
Cash flows from financing activities
Proceeds from sale of common stock, net	122,046	167,387
Proceeds related to issuance of stock for stock-based compensation arrangements, net	744	470
Net cash provided by financing activities	122,790	167,857
Net change in cash and cash equivalents	(3,867)	120,878
Beginning of period	197,945	91,060
End of period	194,078	211,938
Supplemental disclosures
Income taxes paid	0	1,790
Interest paid	1,636	1,641
Non-cash investing and financing activities
Build-to-suit lease transaction

The Company

The Company	9 Months Ended
	Sep. 30, 2017
Organization, Consolidation and Presentation of Financial Statements [Abstract]
The Company	The Company Aerie Pharmaceuticals, Inc. (“Aerie”), with its wholly-owned subsidiaries Aerie Distribution, Inc., Aerie Pharmaceuticals Limited and Aerie Pharmaceuticals Ireland Limited (“Aerie Distribution,” “Aerie Limited” and “Aerie Ireland Limited,” respectively, together with Aerie, the “Company”), is a clinical-stage pharmaceutical company focused on the discovery, development and commercialization of first-in-class therapies for the treatment of patients with glaucoma and other diseases of the eye. The Company has its principal executive offices in Irvine, California, and operates as one business segment. The Company has two advanced-stage product candidates designed to lower intraocular pressure (“IOP”) in patients with open-angle glaucoma or ocular hypertension that it intends to commercialize on its own in North American markets, if approved. The Company’s strategy also includes pursuing regulatory approval for these product candidates in Europe and Japan on its own. The first product candidate, Rhopressa TM (netarsudil ophthalmic solution) 0.02% (“Rhopressa TM ”), is a once-daily eye drop designed to lower IOP in patients with glaucoma or ocular hypertension, which the Company has submitted a New Drug Application (“NDA”) with the U.S. Food and Drug Administration (“FDA”) on February 28, 2017. The Prescription Drug User Fee Act goal date has been set for February 28, 2018. The Company also intends to file for European regulatory approval of Rhopressa TM in the second half of 2018. Additionally, the Company has commenced Phase 1 and Phase 2 clinical trial activities for Rhopressa TM on Japanese patients in the United States and anticipates conducting future Phase 3 clinical trials in Japan with the objective of receiving regulatory approval of Rhopressa TM in Japan. The second product candidate is once-daily Roclatan TM (netarsudil/latanoprost ophthalmic solution) 0.02% / 0.005% (“Roclatan TM ”), a fixed-dose combination of Rhopressa TM and latanoprost for which the Company plans to submit an NDA with the FDA in the second quarter of 2018. The Company is currently conducting a Phase 3 trial named Mercury 3 in Europe comparing Roclatan TM to Ganfort ® , which if successful, is expected to improve its commercialization prospects in that region. Mercury 3 is not necessary for approval in the United States. The Company is also conducting ongoing research to evaluate injectable sustained release formulation technologies with the potential capability of delivering Aerie’s preclinical molecule AR-13154 internally in the eye over several months for the treatment of retinal diseases such as wet age-related macular degeneration (“AMD”) and diabetic macular edema (“DME”), and is also evaluating possible uses for its existing proprietary portfolio of Rho kinase inhibitors beyond ophthalmology. In 2015, the Company revised its corporate structure to align with its business strategy outside of North America by establishing Aerie Limited and Aerie Ireland Limited. Aerie assigned the beneficial rights to its non-U.S. and non-Canadian intellectual property for its lead product candidates to Aerie Limited (the “IP Assignment”). As part of the IP Assignment, Aerie and Aerie Limited entered into a research and development cost-sharing agreement pursuant to which Aerie and Aerie Limited will share the costs of the development of intellectual property and Aerie Limited and Aerie Ireland Limited entered into a license arrangement pursuant to which Aerie Ireland Limited will develop and commercialize the beneficial rights of the intellectual property assigned as part of the IP Assignment. In 2016, Aerie assigned the beneficial rights to certain of Aerie’s intellectual property in the U.S. and Canada to Aerie Distribution, and amended and restated the research and development cost-sharing agreement to transfer Aerie’s rights and obligations under the agreement to Aerie Distribution. The Company has not yet commenced commercial operations and therefore has not generated product revenue. The Company’s activities since inception have primarily consisted of developing product candidates, raising capital and performing research and development activities. The Company does not expect to generate revenue until and unless it receives regulatory approval of and successfully commercializes its current product candidates. The Company has incurred losses and experienced negative operating cash flows since inception. The Company has funded its operations primarily through the sale of equity securities and issuance of convertible notes (Note 7). If the Company does not successfully commercialize any of its current product candidates, it may be unable to generate product revenue or achieve profitability. Accordingly, the Company may be required to obtain further funding through other public or private offerings, debt financing, collaboration and licensing arrangements or other sources. Adequate additional funding may not be available to the Company on acceptable terms, or at all. If the Company is unable to raise capital when needed or on attractive terms, it may be forced to delay, reduce or eliminate its research and development programs or commercialization efforts.

Significant Accounting Policies

Significant Accounting Policies	9 Months Ended
	Sep. 30, 2017
Accounting Policies [Abstract]
Significant Accounting Policies	Significant Accounting Policies Basis of Presentation The Company’s interim condensed consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“U.S. GAAP”). In the opinion of management, the Company has made all necessary adjustments, which include normal recurring adjustments necessary for a fair statement of the Company’s consolidated financial position and results of operations for the interim periods presented. Certain information and disclosures normally included in the annual consolidated financial statements prepared in accordance with U.S. GAAP have been condensed or omitted. These interim condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements and accompanying notes for the year ended December 31, 2016 included in the Company’s Annual Report on Form 10-K filed with the Securities and Exchange Commission (“SEC”) on March 9, 2017. The results for the three and nine months ended September 30, 2017 are not necessarily indicative of the results to be expected for a full year, any other interim periods or any future year or period. Principles of Consolidation The interim condensed consolidated financial statements include the accounts of Aerie and its wholly-owned subsidiaries. All intercompany accounts, transactions and profits have been eliminated in consolidation. Use of Estimates The preparation of consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the consolidated financial statements and reported amounts of income and expenses during the reporting periods. Significant items subject to such estimates and assumptions include the valuation of stock options and operating expense accruals. Actual results could differ from the Company’s estimates. Investments The Company determines the appropriate classification of its investments in debt and equity securities at the time of purchase. The Company’s investments are comprised of certificates of deposit, commercial paper, corporate bonds and government agency securities that are classified as available-for-sale in accordance with Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”) 320, Investments—Debt and Equity Securities . The Company classifies investments available to fund current operations as current assets on its consolidated balance sheets. Investments are classified as long-term assets on the consolidated balance sheets if (i) the Company has the intent and ability to hold the investments for a period of at least one year and (ii) the contractual maturity date of the investments is greater than one year. Available-for-sale investments are recorded at fair value, with unrealized gains or losses included in comprehensive loss on the condensed consolidated statements of operations and comprehensive loss and in accumulated other comprehensive loss on the condensed consolidated balance sheets. Realized gains and losses are determined using the specific identification method and are included as a component of other income (expense), net (Note 3). There were no realized gains or losses recognized for the three and nine months ended September 30, 2017 or 2016 . The Company reviews investments for other-than-temporary impairment whenever the fair value of an investment is less than the amortized cost and evidence indicates that an investment’s carrying amount is not recoverable within a reasonable period of time. To determine whether an impairment is other-than-temporary, the Company considers its intent to sell, or whether it is more likely than not that the Company will be required to sell the investment before recovery of the investment’s amortized cost basis. Evidence considered in this assessment includes reasons for the impairment, the severity and the duration of the impairment and changes in value subsequent to period end. As of September 30, 2017 , there were no investments with a fair value that was significantly lower than the amortized cost basis or any investments that had been in an unrealized loss position for a significant period. Fair Value Measurements The Company records certain financial assets and liabilities at fair value based on the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants. The fair value of the Company’s financial instruments, including cash and cash equivalents and accounts payable, approximate their respective carrying values due to the short-term nature of these instruments. The estimated fair value of the 2014 Convertible Notes (as defined in Note 7) was $269.8 million and $209.6 million as of September 30, 2017 and December 31, 2016 , respectively. The increase in the estimated fair value of the 2014 Convertible Notes was primarily attributable to the increase in the closing price of Aerie’s common stock on September 30, 2017 as compared to December 31, 2016 . Adoption of New Accounting Standards In January 2017, the FASB issued Accounting Standards Update (“ASU”) 2017-01, Business Combinations (Topic 805): Clarifying the Definition of a Business (“ASU 2017-01”) . The new standard clarifies the definition of a business and provides a screen to determine when an integrated set of assets and activities is not a business. The screen requires that when substantially all of the fair value of the gross assets acquired, or disposed of, is concentrated in a single identifiable asset or a group of similar identifiable assets, the set is not a business. The new standard is effective for the Company beginning on January 1, 2018; however, Aerie has elected to early adopt this standard as of July 1, 2017. The adoption of ASU 2017-01 had no impact on the Company’s financial statements for the three and nine months ended September 30, 2017, but may impact the accounting for subsequent business development transactions. See Note 12, “Subsequent Events,” for additional information. Recent Accounting Pronouncements In May 2017, the FASB issued ASU 2017-09, Compensation - Stock Compensation (Topic 718): Scope of Modification Accounting , which clarifies when changes to the terms or conditions of a share-based payment award must be accounted for as modifications. Under ASU 2017-09, an entity will not apply modification accounting to a share-based payment award if the award’s fair value, vesting conditions and classification as an equity or liability instrument are the same immediately before and after the change. ASU 2017-09 will be applied prospectively to awards modified on or after the adoption date. The guidance is effective for the Company beginning on January 1, 2018. Early adoption is permitted. The Company is evaluating the impact of the adoption of this guidance on its consolidated financial statements but does not expect it to have a material impact. In October 2016, the FASB issued ASU 2016-16, Income Taxes (Topic 740): Intra-Entity Transfers of Assets Other Than Inventory , which eliminates the exception to the principle in ASC 740, Income Taxes , that generally requires comprehensive recognition of current and deferred income taxes for all intra-entity sales of assets other than inventory. As a result, a reporting entity would recognize the tax expense from the sale of the asset in the seller’s tax jurisdiction when the transfer occurs, even though the pre-tax effects of that transaction are eliminated in consolidation. The new standard is effective for the Company beginning on January 1, 2018, with early adoption permitted, and must be applied on a modified retrospective basis through a cumulative-effect adjustment directly to retained earnings as of the beginning of the period of adoption. At September 30, 2017, the Company has deferred $2.3 million of income tax effects from past intercompany transactions that are recorded as other assets that it expects to adjust through opening accumulated deficit when the Company adopts the standard on January 1, 2018. In June 2016, the FASB issued ASU 2016-13, Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments , which requires that financial assets measured at amortized cost be presented at the net amount expected to be collected. Currently, U.S. GAAP delays recognition of the full amount of credit losses until the loss is probable of occurring. Under this new standard, the income statement will reflect an entity’s current estimate of all expected credit losses. The measurement of expected credit losses will be based upon historical experience, current conditions, and reasonable and supportable forecasts that affect the collectability of the reported amount. Credit losses relating to available-for-sale debt securities will be recorded through an allowance for credit losses rather than as a direct write-down of the security. The new standard is effective for the Company beginning on January 1, 2020. Early adoption is permitted for fiscal year beginning January 1, 2019. The new guidance prescribes different transition methods for the various provisions. The Company is currently evaluating the impact of this accounting standard update on its consolidated financial statements and disclosures. In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842) , which requires lessees to recognize a right of use asset and related lease liability for those leases classified as operating leases at the commencement date and for those leases that have lease terms of more than 12 months. The guidance is effective for the Company beginning on January 1, 2019, and all annual and interim periods thereafter, with early adoption permitted, and must be adopted using a modified retrospective transition approach for leases that exist or are entered into after the beginning of the earliest comparative period in the financial statements, and provides for certain practical expedients. The Company is currently evaluating the impact of this accounting standard update on the its consolidated financial statements and disclosures. In January 2016, the FASB issued ASU 2016-01, Financial Instruments - Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities , which provides guidance related to the accounting for equity investments, financial liabilities under the fair value option and the presentation and disclosure requirements for financial instruments. The guidance is effective for the Company beginning on January 1, 2018, with early adoption permitted. The new guidance prescribes different transition methods for the various provisions. The Company is currently evaluating the impact of this accounting standard update on the its consolidated financial statements and disclosures, but does not expect it to have a material impact. In May 2014, the FASB issued ASU 2014-09, Revenue from Contracts with Customers (Topic 606) . The standard states that an entity should recognize revenue based on the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The FASB has subsequently issued amendments to ASU 2014-09 that have the same effective date of January 1, 2018. The future impact of ASU 2014-09 will be dependent on the nature of the Company’s future revenue contracts and arrangements, if any. Net Loss per Common Share Basic net loss per common share (“Basic EPS”) is calculated by dividing the net loss by the weighted average number of shares of common stock outstanding for the period, without consideration for potentially dilutive securities with the exception of warrants for common stock with a $0.05 exercise price, which are exercisable for nominal consideration and are therefore included in the calculation of the weighted-average number of shares of common stock as common stock equivalents. Diluted net loss per share (“Diluted EPS”) gives effect to all dilutive potential shares of common stock outstanding during this period. For Diluted EPS, net loss used in calculating Basic EPS is adjusted for certain items related to the dilutive securities. For all periods presented, Aerie’s potential common stock equivalents have been excluded from the computation of Diluted EPS as their inclusion would have had an anti-dilutive effect. The potential common stock equivalents that have been excluded from the computation of Diluted EPS consist of the following: THREE MONTHS ENDED NINE MONTHS ENDED 2017 2016 2017 2016 2014 Convertible Notes (1) 5,040,323 5,040,323 5,040,323 5,040,323 Outstanding stock options 6,237,959 5,152,024 6,237,959 5,152,024 Stock purchase warrants 157,500 157,500 157,500 157,500 Unvested restricted common stock awards 439,549 171,734 439,549 171,734 (1) Conversion is limited to a 9.985% ownership cap in shares of common stock by the holder. In addition to the common stock equivalents presented above, the 2014 Convertible Notes provide for an increase in the conversion rate if conversion is elected in connection with a significant corporate transaction. Refer to Note 7 for further information regarding the 2014 Convertible Notes.

Other Income (Expense), Net

Other Income (Expense), Net	9 Months Ended
	Sep. 30, 2017
Other Income and Expenses [Abstract]
Other Income (Expense), Net	Other Income (Expense), Net Other income (expense), net consists of the following: THREE MONTHS ENDED NINE MONTHS ENDED (in thousands) 2017 2016 2017 2016 Interest and amortization expense $ (597 ) $ (600 ) $ (1,799 ) $ (1,910 ) Foreign exchange loss (163 ) (4 ) (565 ) (14 ) Investment income 619 144 1,293 434 $ (141 ) $ (460 ) $ (1,071 ) $ (1,490 ) The foreign exchange loss during the three and nine months ended September 30, 2017 is primarily related to the remeasurement of the Company’s Euro-denominated monetary liability related to its build-to-suit lease obligation (Note 8), which is held by a subsidiary with a U.S. dollar functional currency.

Investments

Investments	9 Months Ended
	Sep. 30, 2017
Investments, Debt and Equity Securities [Abstract]
Investments	Investments Cash, cash equivalents and investments as of September 30, 2017 included the following: (in thousands) AMORTIZED COST GROSS UNREALIZED GAINS GROSS UNREALIZED LOSSES FAIR VALUE Cash and cash equivalents: Cash and money market funds $ 194,078 $ — $ — $ 194,078 Total cash and cash equivalents $ 194,078 $ — $ — $ 194,078 Investments: Commercial paper (due within 1 year) $ 43,225 $ — $ — $ 43,225 Corporate bonds (due within 1 year) 44,125 — (94 ) 44,031 Corporate bonds (due within 2 years) 905 — (4 ) 901 Total investments $ 88,255 $ — $ (98 ) $ 88,157 Total cash, cash equivalents and investments $ 282,333 $ — $ (98 ) $ 282,235 Cash, cash equivalents and investments as of December 31, 2016 included the following: (in thousands) AMORTIZED COST GROSS UNREALIZED GAINS GROSS UNREALIZED LOSSES FAIR VALUE Cash and cash equivalents: Cash and money market funds $ 196,445 $ — $ — $ 196,445 Commercial paper 1,500 — — 1,500 Total cash and cash equivalents $ 197,945 $ — $ — $ 197,945 Investments: Certificates of deposit (due within 1 year) $ 6,920 $ 4 $ (1 ) $ 6,923 Corporate bonds (due within 1 year) 27,615 4 (75 ) 27,544 Government agencies (due within 1 year) 1,250 — — 1,250 Total investments $ 35,785 $ 8 $ (76 ) $ 35,717 Total cash, cash equivalents and investments $ 233,730 $ 8 $ (76 ) $ 233,662

Fair Value Measurements

Fair Value Measurements	9 Months Ended
	Sep. 30, 2017
Fair Value Disclosures [Abstract]
Fair Value Measurements	Fair Value Measurements The Company records certain financial assets and liabilities at fair value in accordance with the provisions of ASC 820 on fair value measurements. As defined in the guidance, fair value, defined as an exit price, represents the amount that would be received to sell an asset or pay to transfer a liability in an orderly transaction between market participants. As a result, fair value is a market-based approach that should be determined based on assumptions that market participants would use in pricing an asset or a liability. As a basis for considering these assumptions, the guidance defines a three-tier value hierarchy that prioritizes the inputs used in the valuation methodologies in measuring fair value. • Level 1—Unadjusted quoted prices in active, accessible markets for identical assets or liabilities. • Level 2—Other inputs that are directly or indirectly observable in the marketplace. • Level 3—Unobservable inputs that are supported by little or no market activity. The fair value hierarchy also requires an entity to maximize the use of observable inputs and minimize the use of unobservable inputs when measuring fair value. The following tables summarize the fair value of financial assets and liabilities that are measured at fair value and the classification by level of input within the fair value hierarchy: FAIR VALUE MEASUREMENTS AS OF SEPTEMBER 30, 2017 (in thousands) Level 1 Level 2 Level 3 Total Cash and cash equivalents: Cash and money market funds $ 194,078 $ — $ — $ 194,078 Total cash and cash equivalents $ 194,078 $ — $ — $ 194,078 Investments: Commercial paper $ — $ 43,225 $ — $ 43,225 Corporate bonds — 44,932 — 44,932 Total investments $ — $ 88,157 $ — $ 88,157 Total cash, cash equivalents and investments $ 194,078 $ 88,157 $ — $ 282,235 FAIR VALUE MEASUREMENTS AS OF DECEMBER 31, 2016 (in thousands) Level 1 Level 2 Level 3 Total Cash and cash equivalents: Cash and money market funds $ 196,445 $ — $ — $ 196,445 Commercial paper — 1,500 — 1,500 Total cash and cash equivalents $ 196,445 $ 1,500 $ — $ 197,945 Investments: Certificates of deposit $ — $ 6,923 $ — $ 6,923 Corporate bonds — 27,544 — 27,544 Government agencies — 1,250 — 1,250 Total investments $ — $ 35,717 $ — $ 35,717 Total cash, cash equivalents and investments $ 196,445 $ 37,217 $ — $ 233,662 Convertible Notes As of September 30, 2017 and December 31, 2016 , the estimated fair value of the 2014 Convertible Notes was $269.8 million and $209.6 million , respectively. The estimated fair value of the 2014 Convertible Notes was determined using a scenario analysis and Monte Carlo simulation model to capture the various features of the 2014 Convertible Notes. The scenario analysis and Monte Carlo simulation require the use of Level 3 unobservable inputs and subjective assumptions, including but not limited to the probability of conversion, stock price volatility, the risk-free interest rate and credit spread. The increase in the estimated fair value of the 2014 Convertible Notes was primarily attributable to the increase in the closing price of Aerie’s common stock on September 30, 2017 as compared to December 31, 2016 . The estimates presented are not necessarily indicative of amounts that could be realized in a current market exchange. The use of alternative market assumptions and estimation methodologies could have a material effect on these estimates of fair value.

Accounts Payable & Other Curren

Accounts Payable & Other Current Liabilities	9 Months Ended
	Sep. 30, 2017
Payables and Accruals [Abstract]
Accounts Payable & Other Current Liabilities	Accounts Payable & Other Current Liabilities Accounts payable and other current liabilities consist of the following: (in thousands) SEPTEMBER 30, 2017 DECEMBER 31, 2016 Accounts payable $ 3,651 $ 5,610 Accrued expenses and other current liabilities: Employee benefits and compensation related accruals (1) 4,585 4,111 Selling, general and administrative related accruals (2) 6,853 2,908 Research and development related accruals (3) 2,956 6,191 $ 18,045 $ 18,820 (1) Comprised of accrued bonus, accrued vacation and other employee-related expenses. (2) Comprised of accruals such as outside professional fees, accruals related to commercial manufacturing activities and other business-related expenses. (3) Comprised of accruals such as fees for investigative sites, contract research organizations, contract manufacturing organizations and other service providers that assist in conducting preclinical research studies and clinical trials.

Convertible Notes

Convertible Notes	9 Months Ended
	Sep. 30, 2017
Debt Disclosure [Abstract]
Convertible Notes	Convertible Notes On September 30, 2014, Aerie issued $125.0 million aggregate principal amount of senior secured convertible notes (“the 2014 Convertible Notes”) to Deerfield Partners, L.P., Deerfield International Master Fund, L.P., Deerfield Private Design Fund III, L.P., Deerfield Special Situations Fund, L.P. and Deerfield Special Situations International Master Fund, L.P. On January 1, 2015, Deerfield Special Situations International Master Fund, L.P. transferred all of its rights under the 2014 Convertible Notes to Deerfield Special Situations Fund, L.P. (together with the other Deerfield entities listed above, “Deerfield”). The 2014 Convertible Notes were issued pursuant to a note purchase agreement (as amended and supplemented from time to time, the “Note Purchase Agreement”), dated as of September 8, 2014, among Aerie and the Deerfield entities party thereto. The 2014 Convertible Notes bear interest at a rate of 1.75% per annum payable quarterly in arrears on the first business day of each January, April, July and October. The 2014 Convertible Notes mature on the seventh anniversary from the date of issuance , unless earlier converted. The 2014 Convertible Notes are guaranteed on a senior secured basis by Aerie Distribution. The 2014 Convertible Notes constitute the senior secured obligations of Aerie and Aerie Distribution, collateralized by a first priority security interest in substantially all of the assets of Aerie and Aerie Distribution. The Note Purchase Agreement provides that, upon the request of Aerie, Deerfield will release all of the liens on the collateral and the security agreement will terminate if both of the following occur: (i) beginning one month after FDA approval of either Rhopressa TM or Roclatan TM , shares of Aerie’s common stock have traded at a price above $30 per share (subject to adjustment for any subdivision or combination of outstanding common stock) for 30 consecutive trading days, and (ii) Aerie is prepared to close a financing that will be secured by a lien on Aerie’s assets, subject only to the release of the lien on Aerie’s assets held by Deerfield. The 2014 Convertible Notes are convertible at any time at the option of Deerfield, in whole or in part, into shares of common stock, including upon the repayment of the 2014 Convertible Notes at maturity (the “Conversion Option”). However, upon conversion, Deerfield (together with their affiliates) is limited to a 9.985% ownership cap in shares of common stock (the “ 9.985% Cap”). The 9.985% Cap would remain in place upon any assignment of the 2014 Convertible Notes by Deerfield. The initial conversion price is $24.80 per share of common stock (equivalent to an initial conversion rate of 40.32 shares of common stock per $1,000 principal amount of 2014 Convertible Notes), representing a 30% premium over the closing price of the common stock on September 8, 2014. The conversion rate and the corresponding conversion price are subject to adjustment for stock dividends (other than a dividend for which Deerfield would be entitled to participate on an as-converted basis), stock splits, reverse stock splits and reclassifications. In addition, in connection with certain significant corporate transactions, Deerfield, at its option, may (i) require Aerie to prepay all or a portion of the principal amount of the 2014 Convertible Notes, plus accrued and unpaid interest, or (ii) convert all or a portion of the principal amount of the 2014 Convertible Notes into shares of common stock or receive the consideration Deerfield would have received had Deerfield converted the 2014 Convertible Notes immediately prior to the consummation of the transaction. The 2014 Convertible Notes provide for an increase in the conversion rate if Deerfield elects to convert their 2014 Convertible Notes in connection with a significant corporate transaction. The current maximum increase to the initial conversion rate, in connection with a significant corporate transaction, is 12.07 shares of common stock per $1,000 principal amount of 2014 Conversion Notes, which decreases over time and is determined by reference to the price of the common stock prior to the consummation of the significant corporate transaction or the value of the significant corporate transaction. The Note Purchase Agreement contains various representations and warranties, and affirmative and negative covenants, customary for financings of this type, including restrictions on the incurrence of additional debt and liens on Aerie’s and its subsidiaries’ assets. As of September 30, 2017 , Aerie was in compliance with the covenants. The Note Purchase Agreement also provides for certain events of default, including the failure to pay principal and interest when due; inaccuracies in Aerie’s or Aerie Distribution’s representations and warranties to Deerfield; failure to comply with any of the covenants; Aerie’s or Aerie Distribution’s insolvency or the occurrence of certain bankruptcy-related events; certain judgments against Aerie and its subsidiaries; the suspension, cancellation or revocation of governmental authorizations that are reasonably expected to have a material adverse effect on Aerie’s business; the acceleration of a specified amount of indebtedness; and the failure to deliver shares of common stock upon conversion of the 2014 Convertible Notes. If any event of default were to occur, and continue beyond any applicable cure period, the holders of more than 50% of the aggregate principal amount of the then outstanding 2014 Convertible Notes would be permitted to declare the principal and accrued and unpaid interest to be immediately due and payable. The Company recorded the 2014 Convertible Notes as long-term debt at face value less debt discounts relating to fees and certain expenses paid to Deerfield in connection with the transaction. The Conversion Option is a derivative that qualifies for an exemption from bifurcation and liability accounting as provided for in ASC 815, Derivatives and Hedging – Contracts in Entity’s Own Equity (“ASC 815”). Since the Conversion Option is not bifurcated as a derivative pursuant to ASC 815, the Company further evaluated the Conversion Option to determine whether it is considered a beneficial conversion feature (“BCF”). The Company determined that the initial accounting conversion price was greater than the fair value of the common stock at the close of trading on the date of issuance, therefore no BCF existed at inception. However, if Deerfield elects to convert their 2014 Convertible Notes in connection with a significant corporate transaction, the increase to the initial conversion rate may cause a contingent BCF to exist at the time of conversion. The contingent BCF, if any, will be recognized in earnings when the contingency is resolved and will be measured using the fair value of the common stock at the close of trading on the date of issuance and the accounting conversion price as adjusted for such an increase to the initial conversion rate. In connection with the IP Assignment, Aerie granted Deerfield a security interest in certain intercompany promissory notes and pledged 65% of the voting stock of Aerie Limited. Upon the request of Aerie, Deerfield will release the lien on the intercompany promissory notes under certain circumstances. Unamortized debt discounts were $1.2 million as of September 30, 2017 . Debt discounts are amortized using the effective interest method through the earlier of maturity or the conversion of the 2014 Convertible Notes. The table below summarizes the carrying value of the 2014 Convertible Notes as of September 30, 2017 : (in thousands) SEPTEMBER 30, 2017 Gross proceeds $ 125,000 Initial value of issuance costs recorded as debt discount (2,146 ) Amortization of debt discount and issuance costs 915 Carrying value $ 123,769 For the three and nine months ended September 30, 2017 interest expense related to the 2014 Convertible Notes was $0.5 million and $1.6 million , respectively. For the three and nine months ended September 30, 2016 interest expense related to the 2014 Convertible Notes was $0.6 million and $1.6 million , respectively.

Build-to-Suit Lease

Build-to-Suit Lease	9 Months Ended
	Sep. 30, 2017
Leases [Abstract]
Build-to-Suit Lease	Build-to-Suit Lease In January 2017, the Company entered into a Euro-denominated lease agreement, expiring in September 2037, for a new manufacturing plant in Athlone, Ireland, under which the Company is leasing approximately 30,000 square feet of interior floor space for build-out. The Company is permitted to terminate the lease beginning in September 2027. Total expected rental payments, using foreign exchange rates in effect at September 30, 2017 , are approximately $2.7 million through September 2027 and approximately $6.4 million through the expiration of the lease. The Company is not the legal owner of the leased space. However, in accordance with ASC 840, Leases , the Company is deemed to be the owner of the leased space, including the building shell, during the construction period because of the Company’s expected level of direct financial and operational involvement in the substantial tenant improvements required. As a result, the Company capitalized approximately $4.2 million as a build-to-suit asset within property, plant and equipment, net and recognized a corresponding build-to-suit facility lease obligation as a liability on its consolidated balance sheets equal to the estimated replacement cost of the building at the inception of the lease. Additionally, construction costs incurred as part of the build-out and tenant improvements will also be capitalized within property, plant and equipment, net. Costs of approximately $10.0 million have been capitalized through September 30, 2017 related to both equipment purchases and the build-out of the facility. Rental payments made under the lease will be allocated to interest expense and the build-to-suit facility lease obligation based on the implicit rate of the build-to-suit facility lease obligation. The build-to-suit facility lease obligation was approximately $4.8 million as of September 30, 2017 , of which $0.2 million was classified as other current liabilities as of September 30, 2017 . The lease obligation is denominated in Euros and is remeasured to U.S. dollars at the balance sheet date with any foreign exchange gain or loss recognized within other income (expense), net on the condensed consolidated statements of operations and comprehensive loss. Unrealized foreign currency loss related to the remeasurement of the lease obligation for the three and nine months ended September 30, 2017 was $0.2 million and $0.5 million , respectively.

Stockholders' Equity

Stockholders' Equity	9 Months Ended
	Sep. 30, 2017
Equity [Abstract]
Stockholders' Equity	Stockholders’ Equity From the Company’s initial public offering (“IPO”) through December 31, 2016, the Company has issued and sold (1) a total of 5,933,712 shares of common stock under its “at-the-market” sales agreements and received net proceeds of approximately $146.6 million , after deducting commissions at a rate of up to 3% of the gross sales price per share sold and other fees and expenses, and (2) 2,542,373 shares of common stock pursuant to an underwriting agreement, dated September 15, 2016, for which the Company received net proceeds of approximately $71.0 million , after deducting the underwriting discount, fees and expenses of approximately $4.0 million . During the nine months ended September 30, 2017 , the Company has issued and sold 906,858 shares of common stock under its “at-the-market” sales agreement, for which the Company received net proceeds of approximately $49.3 million , after deducting commissions, fees and expenses of $0.6 million . Further, on May 25, 2017, the Company entered into an underwriting agreement relating to the registered public offering of 1,395,349 shares of the Company’s common stock at a price to the public of $53.75 per share. The Company received net proceeds of approximately $72.7 million , after deducting underwriting discounts, fees and expenses of $2.3 million . Warrants As of September 30, 2017 , the Company also has the following equity-classified warrants to purchase common stock outstanding: NUMBER OF UNDERLYING SHARES EXERCISE PRICE PER SHARE WARRANT EXPIRATION DATE 75,000 $ 5.00 February 2019 75,000 $ 5.00 November 2019 7,500 $ 5.00 August 2020 223,482 $ 0.05 December 2019 The warrants outstanding as of September 30, 2017 are all currently exercisable with a weighted-average remaining life of 2.0 years .

Stock-based Compensation

Stock-based Compensation	9 Months Ended
	Sep. 30, 2017
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock-based Compensation	Stock-based Compensation Stock-based compensation expense for options and restricted stock awards (“RSAs”) is reflected in the condensed consolidated statements of operations and comprehensive loss as follows: THREE MONTHS ENDED NINE MONTHS ENDED (in thousands) 2017 2016 2017 2016 Selling, general and administrative $ 4,995 $ 3,406 $ 14,032 $ 9,295 Research and development 1,562 693 4,040 2,219 Total $ 6,557 $ 4,099 $ 18,072 $ 11,514 The estimated fair value of options to purchase common stock is determined on the date of grant using the Black-Scholes option pricing model. Options granted to non-employees are revalued at each financial reporting period until the required service is performed. The fair value of RSAs granted is based on the market value of Aerie’s common stock on the date of grant. Compensation expense related to time-based RSAs is expensed on a straight-line basis over the vesting period. For RSAs with non-market performance conditions, the Company evaluates the criteria for each grant to determine the probability that the performance condition will be achieved. Compensation expense for RSAs with non-market performance conditions is recognized over the respective service period when it is deemed probable that the performance condition will be satisfied. As of September 30, 2017 , the Company had $51.9 million of unrecognized compensation expense related to options granted under its equity plans. This expense is expected to be recognized over a weighted average period of 2.9 years as of September 30, 2017 . As of September 30, 2017 , the Company had $10.8 million of unrecognized compensation expense, related to unvested RSAs. This expense is expected to be recognized over the weighted average contractual term period of 3.2 years as of September 30, 2017 . Equity Plans The Company maintains three equity compensation plans, the 2005 Aerie Pharmaceutical Stock Plan (the “2005 Plan”), the 2013 Omnibus Incentive Plan (the “2013 Equity Plan”), which was amended and restated as the Aerie Pharmaceuticals, Inc. Amended and Restated Omnibus Incentive Plan (the “Amended and Restated Equity Plan”), as described below, and the Aerie Pharmaceuticals, Inc. Inducement Award Plan (the “Inducement Award Plan”), as described below. The 2005 Plan, the Amended and Restated Equity Plan and the Inducement Award Plan are referred to collectively as the “Plans.” On October 30, 2013, the effective date of the 2013 Equity Plan, the 2005 Plan was frozen and no additional awards have been or will be made under the 2005 Plan. Any remaining shares available for future grant under the 2005 Plan were allocated to the 2013 Equity Plan. On April 10, 2015, Aerie’s stockholders approved the adoption of the Amended and Restated Equity Plan and no additional awards have been or will be made under the 2013 Equity Plan. Any remaining shares available under the 2013 Equity Plan were allocated to the Amended and Restated Equity Plan. The Amended and Restated Equity Plan provides for the granting of up to 5,729,068 equity awards in respect of common stock of Aerie, including equity awards that were available for issuance under the 2013 Equity Plan. On December 7, 2016, Aerie’s Board of Directors approved the Inducement Award Plan which provides for the granting of up to 418,000 equity awards in respect of common stock of Aerie, which plan was amended to increase the equity awards that may be issued by 463,500 shares during the nine months ended September 30, 2017 . Awards granted under the Inducement Award Plan are intended to qualify as employment inducement awards under NASDAQ Listing Rule 5635(c)(4). The following table summarizes the stock option activity under the Plans: NUMBER OF WEIGHTED AVERAGE WEIGHTED AGGREGATE Options outstanding at December 31, 2016 5,255,930 $ 14.34 Granted 1,203,459 46.30 Exercised (202,134 ) 11.05 Canceled (19,296 ) 32.82 Options outstanding at September 30, 2017 6,237,959 $ 20.56 7.3 $ 176,569 Options exercisable at September 30, 2017 3,954,715 $ 12.57 6.4 $ 142,558 The following table summarizes the RSA activity under the Plans: NUMBER OF SHARES WEIGHTED AVERAGE FAIR VALUE PER SHARE Nonvested RSAs at December 31, 2016 164,194 $ 19.87 Granted 332,512 47.61 Vested (54,591 ) 20.47 Canceled (2,566 ) 43.90 Nonvested RSAs at September 30, 2017 439,549 $ 40.64 The vesting of time-based RSAs is service-based with terms of one to four years. During the nine months ended September 30, 2017, the Company granted 98,817 RSAs with non-market performance conditions that vest upon the satisfaction of certain performance conditions and service conditions.

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 2017
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies The Company may periodically become subject to legal proceedings and claims arising in connection with its business. The Company is not a party to any known litigation, is not aware of any unasserted claims and does not have contingency reserves established for any litigation liabilities.

Subsequent Events

Subsequent Events	9 Months Ended
	Sep. 30, 2017
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events On October 4, 2017, the Company entered into an Asset Purchase Agreement (the “Agreement”) with Envisia Therapeutics Inc. (“Envisia”) to acquire the rights to use PRINT ® technology in ophthalmology, as well as rights relating to ENV1105, Envisia’s preclinical dexamethasone steroid product candidate for the treatment of diabetic macular edema, which also utilizes the PRINT ® technology. Under the terms of the Agreement, the Company (a) made an upfront cash payment of $10.5 million and issued 263,146 shares of Aerie’s common stock valued at approximately $14.3 million and (b) agreed to make contingent milestone payments, subject to achievement of certain product regulatory approvals. Under the provisions of ASU 2017-01, the Company expects to account for the transaction as an asset acquisition and expects that substantially all of the purchase price will be allocated to acquired in-process research and development and expensed as research and development in the consolidated statement of operations and comprehensive loss during the three months ended December 31, 2017.

Significant Accounting Polici18

Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2017
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation The Company’s interim condensed consolidated financial statements have been prepared in conformity with accounting principles generally accepted in the United States of America (“U.S. GAAP”). In the opinion of management, the Company has made all necessary adjustments, which include normal recurring adjustments necessary for a fair statement of the Company’s consolidated financial position and results of operations for the interim periods presented. Certain information and disclosures normally included in the annual consolidated financial statements prepared in accordance with U.S. GAAP have been condensed or omitted. These interim condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements and accompanying notes for the year ended December 31, 2016 included in the Company’s Annual Report on Form 10-K filed with the Securities and Exchange Commission (“SEC”) on March 9, 2017. The results for the three and nine months ended September 30, 2017 are not necessarily indicative of the results to be expected for a full year, any other interim periods or any future year or period.
Principles of Consolidation	Principles of Consolidation The interim condensed consolidated financial statements include the accounts of Aerie and its wholly-owned subsidiaries. All intercompany accounts, transactions and profits have been eliminated in consolidation.
Use of Estimates	Use of Estimates The preparation of consolidated financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the consolidated financial statements and reported amounts of income and expenses during the reporting periods. Significant items subject to such estimates and assumptions include the valuation of stock options and operating expense accruals. Actual results could differ from the Company’s estimates.
Investments	Investments The Company determines the appropriate classification of its investments in debt and equity securities at the time of purchase. The Company’s investments are comprised of certificates of deposit, commercial paper, corporate bonds and government agency securities that are classified as available-for-sale in accordance with Financial Accounting Standards Board (“FASB”) Accounting Standards Codification (“ASC”) 320, Investments—Debt and Equity Securities . The Company classifies investments available to fund current operations as current assets on its consolidated balance sheets. Investments are classified as long-term assets on the consolidated balance sheets if (i) the Company has the intent and ability to hold the investments for a period of at least one year and (ii) the contractual maturity date of the investments is greater than one year. Available-for-sale investments are recorded at fair value, with unrealized gains or losses included in comprehensive loss on the condensed consolidated statements of operations and comprehensive loss and in accumulated other comprehensive loss on the condensed consolidated balance sheets. Realized gains and losses are determined using the specific identification method and are included as a component of other income (expense), net (Note 3). There were no realized gains or losses recognized for the three and nine months ended September 30, 2017 or 2016 . The Company reviews investments for other-than-temporary impairment whenever the fair value of an investment is less than the amortized cost and evidence indicates that an investment’s carrying amount is not recoverable within a reasonable period of time. To determine whether an impairment is other-than-temporary, the Company considers its intent to sell, or whether it is more likely than not that the Company will be required to sell the investment before recovery of the investment’s amortized cost basis. Evidence considered in this assessment includes reasons for the impairment, the severity and the duration of the impairment and changes in value subsequent to period end.
Fair Value Measurements	Fair Value Measurements The Company records certain financial assets and liabilities at fair value based on the exchange price that would be received for an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants. The fair value of the Company’s financial instruments, including cash and cash equivalents and accounts payable, approximate their respective carrying values due to the short-term nature of these instruments.
Recent Accounting Pronouncements	Recent Accounting Pronouncements In May 2017, the FASB issued ASU 2017-09, Compensation - Stock Compensation (Topic 718): Scope of Modification Accounting , which clarifies when changes to the terms or conditions of a share-based payment award must be accounted for as modifications. Under ASU 2017-09, an entity will not apply modification accounting to a share-based payment award if the award’s fair value, vesting conditions and classification as an equity or liability instrument are the same immediately before and after the change. ASU 2017-09 will be applied prospectively to awards modified on or after the adoption date. The guidance is effective for the Company beginning on January 1, 2018. Early adoption is permitted. The Company is evaluating the impact of the adoption of this guidance on its consolidated financial statements but does not expect it to have a material impact. In October 2016, the FASB issued ASU 2016-16, Income Taxes (Topic 740): Intra-Entity Transfers of Assets Other Than Inventory , which eliminates the exception to the principle in ASC 740, Income Taxes , that generally requires comprehensive recognition of current and deferred income taxes for all intra-entity sales of assets other than inventory. As a result, a reporting entity would recognize the tax expense from the sale of the asset in the seller’s tax jurisdiction when the transfer occurs, even though the pre-tax effects of that transaction are eliminated in consolidation. The new standard is effective for the Company beginning on January 1, 2018, with early adoption permitted, and must be applied on a modified retrospective basis through a cumulative-effect adjustment directly to retained earnings as of the beginning of the period of adoption. At September 30, 2017, the Company has deferred $2.3 million of income tax effects from past intercompany transactions that are recorded as other assets that it expects to adjust through opening accumulated deficit when the Company adopts the standard on January 1, 2018. In June 2016, the FASB issued ASU 2016-13, Financial Instruments - Credit Losses (Topic 326): Measurement of Credit Losses on Financial Instruments , which requires that financial assets measured at amortized cost be presented at the net amount expected to be collected. Currently, U.S. GAAP delays recognition of the full amount of credit losses until the loss is probable of occurring. Under this new standard, the income statement will reflect an entity’s current estimate of all expected credit losses. The measurement of expected credit losses will be based upon historical experience, current conditions, and reasonable and supportable forecasts that affect the collectability of the reported amount. Credit losses relating to available-for-sale debt securities will be recorded through an allowance for credit losses rather than as a direct write-down of the security. The new standard is effective for the Company beginning on January 1, 2020. Early adoption is permitted for fiscal year beginning January 1, 2019. The new guidance prescribes different transition methods for the various provisions. The Company is currently evaluating the impact of this accounting standard update on its consolidated financial statements and disclosures. In February 2016, the FASB issued ASU 2016-02, Leases (Topic 842) , which requires lessees to recognize a right of use asset and related lease liability for those leases classified as operating leases at the commencement date and for those leases that have lease terms of more than 12 months. The guidance is effective for the Company beginning on January 1, 2019, and all annual and interim periods thereafter, with early adoption permitted, and must be adopted using a modified retrospective transition approach for leases that exist or are entered into after the beginning of the earliest comparative period in the financial statements, and provides for certain practical expedients. The Company is currently evaluating the impact of this accounting standard update on the its consolidated financial statements and disclosures. In January 2016, the FASB issued ASU 2016-01, Financial Instruments - Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities , which provides guidance related to the accounting for equity investments, financial liabilities under the fair value option and the presentation and disclosure requirements for financial instruments. The guidance is effective for the Company beginning on January 1, 2018, with early adoption permitted. The new guidance prescribes different transition methods for the various provisions. The Company is currently evaluating the impact of this accounting standard update on the its consolidated financial statements and disclosures, but does not expect it to have a material impact. In May 2014, the FASB issued ASU 2014-09, Revenue from Contracts with Customers (Topic 606) . The standard states that an entity should recognize revenue based on the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The FASB has subsequently issued amendments to ASU 2014-09 that have the same effective date of January 1, 2018. The future impact of ASU 2014-09 will be dependent on the nature of the Company’s future revenue contracts and arrangements, if any.
Net Loss per Common Share	Net Loss per Common Share Basic net loss per common share (“Basic EPS”) is calculated by dividing the net loss by the weighted average number of shares of common stock outstanding for the period, without consideration for potentially dilutive securities with the exception of warrants for common stock with a $0.05 exercise price, which are exercisable for nominal consideration and are therefore included in the calculation of the weighted-average number of shares of common stock as common stock equivalents. Diluted net loss per share (“Diluted EPS”) gives effect to all dilutive potential shares of common stock outstanding during this period. For Diluted EPS, net loss used in calculating Basic EPS is adjusted for certain items related to the dilutive securities. For all periods presented, Aerie’s potential common stock equivalents have been excluded from the computation of Diluted EPS as their inclusion would have had an anti-dilutive effect.

Significant Accounting Polici19

Significant Accounting Policies (Tables)	9 Months Ended
	Sep. 30, 2017
Accounting Policies [Abstract]
Schedule of Computation of Diluted EPS	The potential common stock equivalents that have been excluded from the computation of Diluted EPS consist of the following: THREE MONTHS ENDED NINE MONTHS ENDED 2017 2016 2017 2016 2014 Convertible Notes (1) 5,040,323 5,040,323 5,040,323 5,040,323 Outstanding stock options 6,237,959 5,152,024 6,237,959 5,152,024 Stock purchase warrants 157,500 157,500 157,500 157,500 Unvested restricted common stock awards 439,549 171,734 439,549 171,734 (1) Conversion is limited to a 9.985% ownership cap in shares of common stock by the holder. In addition to the common stock equivalents presented above, the 2014 Convertible Notes provide for an increase in the conversion rate if conversion is elected in connection with a significant corporate transaction. Refer to Note 7 for further information regarding the 2014 Convertible Notes.

Other Income (Expense), Net (Ta

Other Income (Expense), Net (Tables)	9 Months Ended
	Sep. 30, 2017
Other Income and Expenses [Abstract]
Schedule of Other Income (Expense), Net	Other income (expense), net consists of the following: THREE MONTHS ENDED NINE MONTHS ENDED (in thousands) 2017 2016 2017 2016 Interest and amortization expense $ (597 ) $ (600 ) $ (1,799 ) $ (1,910 ) Foreign exchange loss (163 ) (4 ) (565 ) (14 ) Investment income 619 144 1,293 434 $ (141 ) $ (460 ) $ (1,071 ) $ (1,490 ) The foreign exchange loss during the three and nine months ended September 30, 2017 is primarily related to the remeasurement of the Company’s Euro-denominated monetary liability related to its build-to-suit lease obligation (Note 8), which is held by a subsidiary with a U.S. dollar functional currency.

Investments (Tables)

Investments (Tables)	9 Months Ended
	Sep. 30, 2017
Investments, Debt and Equity Securities [Abstract]
Summary of Cash, Cash Equivalents and Investments	Cash, cash equivalents and investments as of September 30, 2017 included the following: (in thousands) AMORTIZED COST GROSS UNREALIZED GAINS GROSS UNREALIZED LOSSES FAIR VALUE Cash and cash equivalents: Cash and money market funds $ 194,078 $ — $ — $ 194,078 Total cash and cash equivalents $ 194,078 $ — $ — $ 194,078 Investments: Commercial paper (due within 1 year) $ 43,225 $ — $ — $ 43,225 Corporate bonds (due within 1 year) 44,125 — (94 ) 44,031 Corporate bonds (due within 2 years) 905 — (4 ) 901 Total investments $ 88,255 $ — $ (98 ) $ 88,157 Total cash, cash equivalents and investments $ 282,333 $ — $ (98 ) $ 282,235 Cash, cash equivalents and investments as of December 31, 2016 included the following: (in thousands) AMORTIZED COST GROSS UNREALIZED GAINS GROSS UNREALIZED LOSSES FAIR VALUE Cash and cash equivalents: Cash and money market funds $ 196,445 $ — $ — $ 196,445 Commercial paper 1,500 — — 1,500 Total cash and cash equivalents $ 197,945 $ — $ — $ 197,945 Investments: Certificates of deposit (due within 1 year) $ 6,920 $ 4 $ (1 ) $ 6,923 Corporate bonds (due within 1 year) 27,615 4 (75 ) 27,544 Government agencies (due within 1 year) 1,250 — — 1,250 Total investments $ 35,785 $ 8 $ (76 ) $ 35,717 Total cash, cash equivalents and investments $ 233,730 $ 8 $ (76 ) $ 233,662

Fair Value Measurements (Tables

Fair Value Measurements (Tables)	9 Months Ended
	Sep. 30, 2017
Fair Value Disclosures [Abstract]
Fair Value Measurements	The following tables summarize the fair value of financial assets and liabilities that are measured at fair value and the classification by level of input within the fair value hierarchy: FAIR VALUE MEASUREMENTS AS OF SEPTEMBER 30, 2017 (in thousands) Level 1 Level 2 Level 3 Total Cash and cash equivalents: Cash and money market funds $ 194,078 $ — $ — $ 194,078 Total cash and cash equivalents $ 194,078 $ — $ — $ 194,078 Investments: Commercial paper $ — $ 43,225 $ — $ 43,225 Corporate bonds — 44,932 — 44,932 Total investments $ — $ 88,157 $ — $ 88,157 Total cash, cash equivalents and investments $ 194,078 $ 88,157 $ — $ 282,235 FAIR VALUE MEASUREMENTS AS OF DECEMBER 31, 2016 (in thousands) Level 1 Level 2 Level 3 Total Cash and cash equivalents: Cash and money market funds $ 196,445 $ — $ — $ 196,445 Commercial paper — 1,500 — 1,500 Total cash and cash equivalents $ 196,445 $ 1,500 $ — $ 197,945 Investments: Certificates of deposit $ — $ 6,923 $ — $ 6,923 Corporate bonds — 27,544 — 27,544 Government agencies — 1,250 — 1,250 Total investments $ — $ 35,717 $ — $ 35,717 Total cash, cash equivalents and investments $ 196,445 $ 37,217 $ — $ 233,662

Accounts Payable & Other Curr23

Accounts Payable & Other Current Liabilities (Tables)	9 Months Ended
	Sep. 30, 2017
Payables and Accruals [Abstract]
Summary of Accounts Payable and Other Current Liabilities	Accounts payable and other current liabilities consist of the following: (in thousands) SEPTEMBER 30, 2017 DECEMBER 31, 2016 Accounts payable $ 3,651 $ 5,610 Accrued expenses and other current liabilities: Employee benefits and compensation related accruals (1) 4,585 4,111 Selling, general and administrative related accruals (2) 6,853 2,908 Research and development related accruals (3) 2,956 6,191 $ 18,045 $ 18,820 (1) Comprised of accrued bonus, accrued vacation and other employee-related expenses. (2) Comprised of accruals such as outside professional fees, accruals related to commercial manufacturing activities and other business-related expenses. (3) Comprised of accruals such as fees for investigative sites, contract research organizations, contract manufacturing organizations and other service providers that assist in conducting preclinical research studies and clinical trials.

Convertible Notes (Tables)

Convertible Notes (Tables)	9 Months Ended
	Sep. 30, 2017
Debt Disclosure [Abstract]
Summary of Carrying Value of Convertible Notes	The table below summarizes the carrying value of the 2014 Convertible Notes as of September 30, 2017 : (in thousands) SEPTEMBER 30, 2017 Gross proceeds $ 125,000 Initial value of issuance costs recorded as debt discount (2,146 ) Amortization of debt discount and issuance costs 915 Carrying value $ 123,769

Stockholders' Equity (Tables)

Stockholders' Equity (Tables)	9 Months Ended
	Sep. 30, 2017
Equity [Abstract]
Schedule of Equity Classified Warrants Outstanding	As of September 30, 2017 , the Company also has the following equity-classified warrants to purchase common stock outstanding: NUMBER OF UNDERLYING SHARES EXERCISE PRICE PER SHARE WARRANT EXPIRATION DATE 75,000 $ 5.00 February 2019 75,000 $ 5.00 November 2019 7,500 $ 5.00 August 2020 223,482 $ 0.05 December 2019

Stock-based Compensation (Table

Stock-based Compensation (Tables)	9 Months Ended
	Sep. 30, 2017
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Stock-Based Compensation Expense for Options Granted, Restricted Stock and Stock Purchase Rights as Reflected in Statement of Operations	Stock-based compensation expense for options and restricted stock awards (“RSAs”) is reflected in the condensed consolidated statements of operations and comprehensive loss as follows: THREE MONTHS ENDED NINE MONTHS ENDED (in thousands) 2017 2016 2017 2016 Selling, general and administrative $ 4,995 $ 3,406 $ 14,032 $ 9,295 Research and development 1,562 693 4,040 2,219 Total $ 6,557 $ 4,099 $ 18,072 $ 11,514
Schedule of Stock Options Activity	The following table summarizes the stock option activity under the Plans: NUMBER OF WEIGHTED AVERAGE WEIGHTED AGGREGATE Options outstanding at December 31, 2016 5,255,930 $ 14.34 Granted 1,203,459 46.30 Exercised (202,134 ) 11.05 Canceled (19,296 ) 32.82 Options outstanding at September 30, 2017 6,237,959 $ 20.56 7.3 $ 176,569 Options exercisable at September 30, 2017 3,954,715 $ 12.57 6.4 $ 142,558
Restricted Stock and Restricted Stock Units Activity	The following table summarizes the RSA activity under the Plans: NUMBER OF SHARES WEIGHTED AVERAGE FAIR VALUE PER SHARE Nonvested RSAs at December 31, 2016 164,194 $ 19.87 Granted 332,512 47.61 Vested (54,591 ) 20.47 Canceled (2,566 ) 43.90 Nonvested RSAs at September 30, 2017 439,549 $ 40.64

The Company - Additional Inform

The Company - Additional Information (Detail)	9 Months Ended
	Sep. 30, 2017Segment
Organization, Consolidation and Presentation of Financial Statements [Line Items]
Number of operating segments	1
Rhopressa
Organization, Consolidation and Presentation of Financial Statements [Line Items]
Percentage of dosage designed to lower intraocular pressure	0.02%
Latanoprost
Organization, Consolidation and Presentation of Financial Statements [Line Items]
Percentage of dosage designed to lower intraocular pressure	0.005%

Significant Accounting Polici28

Significant Accounting Policies - Additional Information (Detail) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Gross realized gain (loss)	$ 0	$ 0	$ 0	$ 0
Investments owned, at fair value			0
Long-term debt, fair value	$ 269,800,000		$ 269,800,000		$ 209,600,000
Warrants exercise price (in dollars per share)	$ 0.05		$ 0.05
Accounting Standards Update 2016-16, Income Tax Effects Recorded As Other Assets | Retained Earnings
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Income tax effects from past intercompany transactions	$ 2,300,000		$ 2,300,000

Significant Accounting Polici29

Significant Accounting Policies - Schedule of Computation of Diluted EPS (Detail) - shares	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Ownership cap in shares of common stock (as a percentage)	9.985%		9.985%
Outstanding stock options
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potential common stock equivalents excluded from the computation of diluted net loss per share (in shares)	6,237,959	5,152,024	6,237,959	5,152,024
Stock purchase warrants
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potential common stock equivalents excluded from the computation of diluted net loss per share (in shares)	157,500	157,500	157,500	157,500
Unvested restricted common stock awards
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potential common stock equivalents excluded from the computation of diluted net loss per share (in shares)	439,549	171,734	439,549	171,734
Convertible notes
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potential common stock equivalents excluded from the computation of diluted net loss per share (in shares)	5,040,323	5,040,323	5,040,323	5,040,323
Ownership cap in shares of common stock (as a percentage)	9.985%		9.985%

Other Income (Expense), Net - S

Other Income (Expense), Net - Schedule of Other Income (Expense), Net (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Other Income and Expenses [Abstract]
Interest and amortization expense	$ (597)	$ (600)	$ (1,799)	$ (1,910)
Foreign exchange loss	(163)	(4)	(565)	(14)
Investment income	619	144	1,293	434
Other income (expense), net	$ (141)	$ (460)	$ (1,071)	$ (1,490)

Investments - Summary of Cash,

Investments - Summary of Cash, Cash Equivalents and Investments (Detail) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016	Sep. 30, 2016	Dec. 31, 2015
Cash and cash equivalents:
AMORTIZED COST	$ 194,078	$ 197,945	$ 211,938	$ 91,060
FAIR VALUE	194,078	197,945
Investments:
AMORTIZED COST	282,333	233,730
GROSS UNREALIZED GAINS	0	8
GROSS UNREALIZED LOSSES	(98)	(76)
FAIR VALUE	282,235	233,662
Cash and money market funds
Cash and cash equivalents:
AMORTIZED COST	194,078	196,445
FAIR VALUE	194,078	196,445
Commercial paper
Cash and cash equivalents:
AMORTIZED COST		1,500
FAIR VALUE		1,500
Commercial paper
Investments:
AMORTIZED COST	43,225
GROSS UNREALIZED GAINS	0
GROSS UNREALIZED LOSSES	0
FAIR VALUE	43,225
Total investments
Investments:
AMORTIZED COST	88,255	35,785
GROSS UNREALIZED GAINS	0	8
GROSS UNREALIZED LOSSES	(98)	(76)
FAIR VALUE	88,157	35,717
Certificates of deposit (due within 1 year)
Investments:
AMORTIZED COST		6,920
GROSS UNREALIZED GAINS		4
GROSS UNREALIZED LOSSES		(1)
FAIR VALUE		6,923
Corporate bonds (due within 1 year)
Investments:
AMORTIZED COST	44,125	27,615
GROSS UNREALIZED GAINS	0	4
GROSS UNREALIZED LOSSES	(94)	(75)
FAIR VALUE	44,031	27,544
Corporate bonds (due within 2 years)
Investments:
AMORTIZED COST	905
GROSS UNREALIZED GAINS	0
GROSS UNREALIZED LOSSES	(4)
FAIR VALUE	$ 901
Government agencies
Investments:
AMORTIZED COST		1,250
GROSS UNREALIZED GAINS		0
GROSS UNREALIZED LOSSES		0
FAIR VALUE		$ 1,250

Fair Value Measurements - Summa

Fair Value Measurements - Summary of Fair Value of Financial Assets and Liabilities that are Measured at Fair Value and the Classification by Level of Input within Fair Value Hierarchy (Detail) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total cash and cash equivalents	$ 194,078	$ 197,945
Total investments	88,157	35,717
Total cash, cash equivalents and investments	282,235	233,662
Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total cash and cash equivalents	194,078	196,445
Total investments	0	0
Total cash, cash equivalents and investments	194,078	196,445
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total cash and cash equivalents	0	1,500
Total investments	88,157	35,717
Total cash, cash equivalents and investments	88,157	37,217
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total investments	0	0
Total cash, cash equivalents and investments	0	0
Commercial paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total investments	43,225
Commercial paper | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total investments	43,225
Certificates of deposit
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total investments		6,923
Certificates of deposit | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total investments		6,923
Corporate bonds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total investments	44,932	27,544
Corporate bonds | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total investments	44,932	27,544
Government agencies
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total investments		1,250
Government agencies | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total investments		1,250
Cash and money market funds
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total cash and cash equivalents	194,078	196,445
Cash and money market funds | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total cash and cash equivalents	$ 194,078	196,445
Commercial paper
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total cash and cash equivalents		1,500
Commercial paper | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total cash and cash equivalents		0
Commercial paper | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total cash and cash equivalents		$ 1,500

Fair Value Measurements - Addit

Fair Value Measurements - Additional Information (Detail) - USD ($) $ in Millions	Sep. 30, 2017	Dec. 31, 2016
Fair Value Disclosures [Abstract]
Long-term debt, fair value	$ 269.8	$ 209.6

Accounts Payable & Other Curr34

Accounts Payable & Other Current Liabilities - Summary of Accounts Payable and Other Current Liabilities (Detail) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Payables and Accruals [Abstract]
Accounts payable	$ 3,651	$ 5,610
Accrued expenses and other liabilities:
Employee benefits and compensation related accruals	4,585	4,111
Selling, general and administrative related accruals	6,853	2,908
Research and development related accruals	2,956	6,191
Accounts payable and other accrued liabilities	$ 18,045	$ 18,820

Convertible Notes - Additional

Convertible Notes - Additional Information (Detail)	1 Months Ended	3 Months Ended		9 Months Ended
	Mar. 31, 2015	Sep. 30, 2017USD ($)$ / sharesshares	Sep. 30, 2016USD ($)	Sep. 30, 2017USD ($)$ / sharesshares	Sep. 30, 2016USD ($)	Sep. 30, 2014USD ($)d$ / shares
Debt Instrument [Line Items]
Aggregate amount of senior notes issued		$ 125,000,000		$ 125,000,000
Debt instrument, anniversary term				7 years
Debt instrument, convertible, ownership cap in shares of common stock (as a percentage)		9.985%		9.985%
Convertible notes
Debt Instrument [Line Items]
Aggregate amount of senior notes issued						$ 125,000,000
Debt instrument, interest rate percentage						1.75%
Debt instrument, convertible, stock price trigger (in dollars per share) | $ / shares						$ 30
Debt instrument, convertible, threshold trading days | d						30
Debt instrument, transaction fee						$ 600,000
Reimbursed expenses incurred by Deerfield in connection with transaction						300,000
Legal and advisory fees						$ 1,300,000
Debt instrument, convertible, ownership cap in shares of common stock (as a percentage)		9.985%		9.985%
Debt instrument, convertible, initial conversion price per share (in dollars per share) | $ / shares		$ 24.80		$ 24.80
Debt instrument, convertible, common stock conversion rate per $1,000 principal amount				0.04032
Debt instrument, convertible, conversion premium percentage		30.00%		30.00%
Debt instrument, convertible, maximum increase to the initial conversion rate per $1,000 principal amount (in shares) | shares		0.01207		0.01207
Debt instrument, convertible, ownership percentage threshold necessary to declare principal and accrued interest payable (more than)		50.00%		50.00%
Unamortized debt discounts and debt issuance cost		$ (1,200,000)		$ (1,200,000)
Interest expense related to convertible notes		$ 500,000	$ 600,000	$ 1,600,000	$ 1,600,000
Subsidiaries | Convertible notes
Debt Instrument [Line Items]
Business acquisition, percentage of voting interests acquired	65.00%

Convertible Notes - Summary of

Convertible Notes - Summary of Carrying Value of Convertible Notes (Detail) - USD ($)	Sep. 30, 2017	Dec. 31, 2016
Debt Disclosure [Abstract]
Gross proceeds	$ 125,000,000
Initial value of issuance costs recorded as debt discount	(2,146,000)
Amortization of debt discount and issuance costs	915,000
Carrying value	$ 123,769,000	$ 123,539,000

Build-to-Suit Lease - Narrative

Build-to-Suit Lease - Narrative (Details) $ in Millions	1 Months Ended	3 Months Ended	9 Months Ended		129 Months Ended	249 Months Ended
	Jan. 31, 2017USD ($)ft²	Sep. 30, 2017USD ($)	Sep. 30, 2017USD ($)	Sep. 30, 2017USD ($)	Sep. 30, 2027USD ($)	Sep. 30, 2037USD ($)
Operating Leased Assets [Line Items]
Area of interior floor space (in sqft) | ft²	30,000
Build-to-suit facility lease obligation		$ 4.8	$ 4.8	$ 4.8
Foreign exchange loss		0.2		0.5
Scenario, Forecast
Operating Leased Assets [Line Items]
Total rent expense					$ 2.7	$ 6.4
Property, Plant and Equipment
Operating Leased Assets [Line Items]
Capitalized amount of build-to-suit asset	$ 4.2		10
Other Current Liabilities
Operating Leased Assets [Line Items]
Build-to-suit facility lease obligation		$ 0.2	$ 0.2	$ 0.2

Stockholders' Equity - Addition

Stockholders' Equity - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands	May 25, 2017	Sep. 15, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Class of Stock [Line Items]
Proceeds from sale of common stock, net			$ 122,046	$ 167,387
Weighted-average remaining lives			2 years 7 days
Common stock
Class of Stock [Line Items]
Common stock issued and sold under sales agreement (in shares)			906,858		5,933,712
Proceeds from sale of common stock, net	$ 72,700	$ 71,000	$ 49,300		$ 146,600
Percentage of gross sales commissions (up to)					3.00%
Stock issued during period (in shares)	1,395,349	2,542,373
Underwriting discounts, fees and expenses	$ 2,300	$ 4,000	$ 600
Price per share issued under underwriting agreement (in dollars per share)	$ 53.75

Stockholders' Equity - Schedule

Stockholders' Equity - Schedule of Equity Classified Warrants Outstanding (Detail)	Sep. 30, 2017$ / sharesshares
Class of Warrant or Right [Line Items]
EXERCISE PRICE PER SHARE (in dollars per share)	$ 0.05
February 2019 | Common stock
Class of Warrant or Right [Line Items]
NUMBER OF UNDERLYING SHARES (in shares) | shares	75,000
EXERCISE PRICE PER SHARE (in dollars per share)	$ 5
November 2019 | Common stock
Class of Warrant or Right [Line Items]
NUMBER OF UNDERLYING SHARES (in shares) | shares	75,000
EXERCISE PRICE PER SHARE (in dollars per share)	$ 5
August 2020 | Common stock
Class of Warrant or Right [Line Items]
NUMBER OF UNDERLYING SHARES (in shares) | shares	7,500
EXERCISE PRICE PER SHARE (in dollars per share)	$ 5
December 2019 | Common stock
Class of Warrant or Right [Line Items]
NUMBER OF UNDERLYING SHARES (in shares) | shares	223,482
EXERCISE PRICE PER SHARE (in dollars per share)	$ 0.05

Stock-based Compensation - Stoc

Stock-based Compensation - Stock-Based Compensation Expense for Options Granted, Restricted Stock and Stock Purchase Rights as Reflected in Statement of Operations (Detail) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 6,557	$ 4,099	$ 18,072	$ 11,514
Selling, general and administrative
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	4,995	3,406	14,032	9,295
Research and development
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense	$ 1,562	$ 693	$ 4,040	$ 2,219

Stock-based Compensation - Addi

Stock-based Compensation - Additional Information (Detail) $ in Millions	Apr. 10, 2015shares	Oct. 30, 2013shares	Sep. 30, 2017USD ($)planshares	Dec. 07, 2016shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding, weighted average remaining contractual life (in years)			7 years 3 months 1 day
Additional awards granted (in shares)			1,203,459
Unrecognized compensation Expense Related to Options Granted Under its Equity Plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation expense | $			$ 51.9
Compensation cost, weighted average recognition period (in years)			2 years 11 months 9 days
2005 Aerie Pharmaceutical Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of equity compensation plans | plan			3
Additional awards granted (in shares)		0
2013 Omnibus incentive plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Additional awards granted (in shares)	0
Equity awards (up to) (in shares)			5,729,068
Inducement Award Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Equity awards (up to) (in shares)			463,500	418,000
Restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized Compensation expense other than options | $			$ 10.8
Restricted stock awards, weighted average remaining contractual term (in years)			3 years 2 months 5 days
Granted (in shares)			332,512
Restricted stock | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based awards, vesting period (in years)			1 year
Restricted stock | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based awards, vesting period (in years)			4 years
Restricted Stock With Non-Market Performance Conditions
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted (in shares)			98,817

Stock-based Compensation - Sche

Stock-based Compensation - Schedule of Stock Options Activity (Detail) $ / shares in Units, $ in Thousands	9 Months Ended
	Sep. 30, 2017USD ($)$ / sharesshares
NUMBER OF SHARES
Beginning balance (in shares) | shares	5,255,930
Granted (in shares) | shares	1,203,459
Exercised (in shares) | shares	(202,134)
Canceled (in shares) | shares	(19,296)
Ending balance (in shares) | shares	6,237,959
Options exercisable (in shares) | shares	3,954,715
WEIGHTED AVERAGE EXERCISE PRICE
Beginning balance (in dollars per share) | $ / shares	$ 14.34
Granted (in dollars per share) | $ / shares	46.30
Exercised (in dollars per share) | $ / shares	11.05
Cancelled (in dollars per share) | $ / shares	32.82
Ending balance (in dollars per share) | $ / shares	20.56
Options exercisable (in dollars per share) | $ / shares	$ 12.57
WEIGHTED AVERAGE REMAINING CONTRACTUAL LIFE (YEARS)
Options outstanding, weighted average remaining contractual life (in years)	7 years 3 months 1 day
Options exercisable (in years)	6 years 4 months 16 days
AGGREGATE INTRINSIC VALUE
Options outstanding | $	$ 176,569
Options exercisable | $	$ 142,558

Stock-based Compensation - Rest

Stock-based Compensation - Restricted Stock and Restricted Stock Units Activity (Details) - Restricted stock	9 Months Ended
	Sep. 30, 2017$ / sharesshares
NUMBER OF SHARES
Beginning balance (in shares) | shares	164,194
Granted (in shares) | shares	332,512
Vested (in shares) | shares	(54,591)
Canceled (in shares) | shares	(2,566)
Ending balance (in shares) | shares	439,549
WEIGHTED AVERAGE FAIR VALUE PER SHARE
Beginning balance (in dollars per share) | $ / shares	$ 19.87
Granted (in dollars per share) | $ / shares	47.61
Vested (in dollars per share) | $ / shares	20.47
Canceled (in dollars per share) | $ / shares	43.90
Ending balance (in dollars per share) | $ / shares	$ 40.64

Subsequent Events - Narrative (

Subsequent Events - Narrative (Details) - Envisia Therapeutics Inc. - Subsequent Event $ in Millions	Oct. 04, 2017USD ($)shares
Subsequent Event [Line Items]
Cash consideration in business combination	$ 10.5
Shares issued under purchase agreement | shares	263,146
Equity interests exchanged	$ 14.3