Summary of Option Activity (Detail) $ / shares in Units, $ in Thousands	6 Months Ended
	Jun. 30, 2017 USD ($) $ / shares shares
Options Outstanding
Options outstanding at December 31, 2016 | shares	882,748
Granted | shares	101,844
Exercised | shares	(149,903)
Forfeited/cancelled | shares	(31,157)
Options outstanding at June 30, 2017 | shares	803,532
Options exercisable at June 30, 2017 | shares	439,980
Vested and expected to vest at June 30, 2017 | shares	790,545	[1]
Weighted-Average Exercise Price Per Share
Options outstanding at December 31, 2016 | $ / shares	$ 16.88
Granted | $ / shares	33.38
Exercised | $ / shares	10.04
Forfeited/cancelled | $ / shares	20.27
Options outstanding at June 30, 2017 | $ / shares	20.16
Options exercisable at June 30, 2017 | $ / shares	14.98
Vested and expected to vest at June 30, 2017 | $ / shares	$ 20.04	[1]
Weighted-Average Remaining Contractual Term (in years)
Options outstanding at June 30, 2017	6 years 10 months 25 days
Options exercisable at June 30, 2017	5 years 8 months 16 days
Vested and expected to vest at June 30, 2017	6 years 10 months 14 days	[1]
Aggregate Intrinsic Value
Options outstanding at June 30, 2017 | $	$ 17,145
Options exercisable at June 30, 2017 | $	11,695
Vested and expected to vest at June 30, 2017 | $	$ 16,921	[1]

[1] Represents the number of vested options as of June 30, 2017 plus the number of unvested options expected to vest as of June 30, 2017 based on the unvested outstanding options at June 30, 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.