Consolidated Statements of Stockholders' Equity (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Initial Public Offering
Net issuance costs	$ 9,918
Convertible Preferred Stock, Series A
Net issuance costs			$ 2
Convertible Preferred Stock, Series B
Net issuance costs			$ 217
Convertible Preferred Stock, Series C
Net issuance costs		$ 2,208