The Company and Basis of Presentation - Additional Information (Detail) $ / shares in Units, $ in Millions			6 Months Ended
	Jul. 15, 2015 USD ($) $ / shares shares	Jun. 29, 2015	Jun. 30, 2015	Jul. 21, 2015 $ / shares shares
Class of Stock [Line Items]
Convertible preferred stock, conversion basis			On July 21, 2015, immediately prior to the closing of the IPO, all outstanding shares of convertible and redeemable convertible preferred stock converted into 17,971,273 shares of common stock. The IPO closed on July 21, 2015.
Reverse stock split, description			7.45-to-1
Reverse Stock Split, Conversion Ratio		7.45
Reverse stock split, effective date			Jul. 02, 2015
Subsequent Event [Member]
Class of Stock [Line Items]
Common stock issued and sold, price per share				$ 17
Redeemable convertible preferred stock converted into common stock | shares				17,971,273
Initial Public Offering [Member] | Subsequent Event [Member]
Class of Stock [Line Items]
Common stock issued and sold | shares	9,315,000
Common stock issued and sold, price per share	$ 17.00
Proceeds from issuance of common stock, net | $	$ 143.6