Nature of the Business and Basis of Presentation - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Thousands			12 Months Ended
	Jul. 02, 2015	Jun. 26, 2015	Dec. 31, 2015	Dec. 31, 2014	Jul. 01, 2015
Nature Of Business And Basis Of Presentation [Line Items]
Entity incorporated year			Oct. 31, 2010
Entity incorporated state name			State of Delaware
Accumulated deficit			$ 82,612	$ 27,832
Cash, cash equivalents and investments			$ 205,082
Common Stock [Member]
Nature Of Business And Basis Of Presentation [Line Items]
Common stock issued and sold	8,545,138		8,545,138	6,563
Net proceeds from issuance of common stock from IPO after deducting underwriting discounts and commissions	$ 139,267
Conversion of redeemable convertible preferred stock into common stock		22,866,987	22,866,987
Initial Public Offering ("IPO") [Member] | Common Stock [Member]
Nature Of Business And Basis Of Presentation [Line Items]
Public offering price per share		$ 18.00			$ 18.00
Conversion of redeemable convertible preferred stock into common stock		22,866,987
Underwriters Option to Purchase Additional Shares [Member] | Common Stock [Member]
Nature Of Business And Basis Of Presentation [Line Items]
Common stock issued and sold	1,114,583