Formation and Business of the Company - Additional Information (Details) - USD ($) $ / shares in Units, $ in Thousands		1 Months Ended
	Nov. 03, 2015	Mar. 31, 2015	Mar. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Accumulated deficit			$ (73,105)	$ (64,685)
Cash and cash equivalents		$ 35,617	$ 99,495	$ 112,265	$ 43,648
Net proceeds from initial public offering	$ 55,600
Series A, A-1 and Series B Redeemable Convertible Preferred Stock
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Net proceeds from sale of shares of convertible stock		$ 93,900
IPO
Organization Consolidation And Presentation Of Financial Statements [Line Items]
Issuance of common stock	6,253,125
Shares issued, price per share	$ 10.00