Stockholders' Equity - Summary of Stock Option Activity Under the 2010 Stock Plan and the 2013 Stock Plan (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Number of Shares, Outstanding, beginning balance	1,684,783
Number of Shares, Granted	31,216
Number of Shares, Exercised	(167,853)
Number of Shares, Cancelled	(280,817)
Number of Shares, Outstanding, ending balance	1,267,329	1,684,783
Number of Shares, Exercisable as of December 31, 2016	955,971
Number of Shares, Vested and expected to vest at December 31, 2016	1,243,380
Weighted-Average Exercise Price, Outstanding, beginning balance	$ 17.31
Weighted-Average Exercise Price, Granted	19.37
Weighted-Average Exercise Price, Exercised	3.88
Weighted-Average Exercise Price, Cancelled	30.50
Weighted- Average Exercise Price, Outstanding, ending balance	16.22	$ 17.31
Weighted- Average Exercise Price, Exercisable as of December 31, 2016	13.88
Weighted- Average Exercise Price, Vested and expected to vest at December 31, 2016	$ 16.02
Weighted-Average Remaining Contractual Term, Outstanding	6 years 7 months 6 days	7 years 8 months 12 days
Weighted-Average Remaining Contractual Term, Exercisable as of December 31, 2016	6 years 4 months 24 days
Weighted-Average Remaining Contractual Term, Vested and expected to vest at December 31, 2016	6 years 7 months 6 days
Aggregate Intrinsic Value, Outstanding	$ 8,355	$ 13,965
Aggregate Intrinsic Value, Exercisable as of December 31, 2016	7,500
Aggregate Intrinsic Value, Vested and expected to vest at December 31, 2016	$ 8,330