Description of Business - Additional Information (Details) $ / shares in Units, $ in Thousands					12 Months Ended
	Aug. 23, 2016 shares	Jul. 25, 2016 shares	Jul. 19, 2016 USD ($) $ / shares shares	Jul. 07, 2016	Dec. 31, 2016 USD ($) Segment shares	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Organization And Basis Of Presentation [Line Items]
Number of operating business segment | Segment					1
Proceeds from issuance of common stock net of underwriting discount, commission, and offering costs | $					$ 75,208	$ 0	$ 0
Reverse stock split conversion ratio				2.22977
Description of reverse stock split					In July 2016, the Company’s board of directors approved an amendment to the Company’s amended and restated certificate of incorporation to effect a reverse split of the Company’s issued and outstanding common stock and convertible preferred stock at a 2.22977-to-1 ratio, which was effected on July 7, 2016. The par value and authorized shares of common stock and convertible preferred stock were not adjusted as a result of the reverse split.
Accumulated deficit | $					$ (100,411)	$ (40,743)
Common Stock
Organization And Basis Of Presentation [Line Items]
Proceeds from issuance of common stock net of underwriting discount, commission, and offering costs | $			$ 75,200
Convertible preferred stock converted into common stock | shares		13,820,301
Common Stock | Initial Public Offering
Organization And Basis Of Presentation [Line Items]
Sale of stock, shares | shares		5,000,000	5,675,000		5,675,000
Sale of stock price per share | $ / shares			$ 15.00
Common Stock | Underwriters' Option To Purchase
Organization And Basis Of Presentation [Line Items]
Sale of stock, shares | shares	675,000