Summary of Option Activity (Detail) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2017 USD ($) $ / shares shares
Options Outstanding
Options outstanding at December 31, 2016 | shares	882,748
Granted | shares	86,215
Exercised | shares	(137,903)
Forfeited/cancelled | shares	(25,157)
Options outstanding at March 31, 2017 | shares	805,903
Options exercisable at March 31, 2017 | shares	406,859
Vested and expected to vest at March 31, 2017 | shares	791,227	[1]
Weighted-Average Exercise Price Per Share
Options outstanding at December 31, 2016 | $ / shares	$ 16.88
Granted | $ / shares	32.40
Exercised | $ / shares	9.67
Forfeited/cancelled | $ / shares	21.31
Options outstanding at March 31, 2017 | $ / shares	19.68
Options exercisable at March 31, 2017 | $ / shares	14.18
Vested and expected to vest at March 31, 2017 | $ / shares	$ 19.57	[1]
Weighted-Average Remaining Contractual Term (in years)
Options outstanding at March 31, 2017	7 years 29 days
Options exercisable at March 31, 2017	5 years 8 months 23 days
Vested and expected to vest at March 31, 2017	7 years 18 days	[1]
Aggregate Intrinsic Value
Options outstanding at March 31, 2017 | $	$ 12,706
Options exercisable at March 31, 2017 | $	8,659
Vested and expected to vest at March 31, 2017 | $	$ 12,530	[1]

[1] Represents the number of vested options as of March 31, 2017 plus the number of unvested options expected to vest as of March 31, 2017 based on the unvested outstanding options at March 31, 2017 adjusted for estimated forfeiture rates of 8% for awards granted to non-executive level employees and 3% for awards granted to executive level employees.