Warrants - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Sep. 26, 2016	Apr. 30, 2016	Apr. 20, 2016
Class Of Warrant Or Right [Line Items]
Fair value of warrant at the time of conversion	$ (202)	$ (57)	$ (116)
Class B Common Stock
Class Of Warrant Or Right [Line Items]
Common stock issued through cashless exercise of warrant				10,055
Class B Common Stock | Subordinated Loan And Security Agreement
Class Of Warrant Or Right [Line Items]
Warrants issued to purchase shares					21,208
Exercise price of warrant					$ 14.31
Class B Common Stock | Warrant Holder One
Class Of Warrant Or Right [Line Items]
Warrants issued to purchase shares				10,604
Common stock issued through cashless exercise of warrant				3,874
Warrants outstanding	10,604
Subordinated Loan And Security Agreement | Series A Convertible Preferred Stock
Class Of Warrant Or Right [Line Items]
Warrants issued to purchase shares	27,321
Exercise price of warrant	$ 1.37255
Subordinated Loan And Security Agreement | Class B Common Stock
Class Of Warrant Or Right [Line Items]
Warrants issued to purchase shares	27,321
Common stock issued through cashless exercise of warrant				25,658
Senior Credit Facility | Class B Common Stock | Term Loan Borrowings | Warrants Exercise Price at $13.99 | Silicon Valley Bank
Class Of Warrant Or Right [Line Items]
Warrants issued to purchase shares						21,444
Exercise price of warrant						$ 13.99
Senior Credit Facility | Class B Common Stock | Term Loan Borrowings | Warrants Exercise Price at $14.31 | Silicon Valley Bank
Class Of Warrant Or Right [Line Items]
Warrants issued to purchase shares						5,241
Exercise price of warrant						$ 14.31
Additional Paid-In Capital
Class Of Warrant Or Right [Line Items]
Fair value of warrant at the time of conversion	$ 600