Stock-Based Compensation - Stock Option Activity (Detail) - USD ($) $ / shares in Units, $ in Thousands	6 Months Ended	12 Months Ended
	Jun. 30, 2016	Dec. 31, 2015
Options Outstanding
Beginning balance (in shares)	1,097,323
Granted (in shares)	94,115
Exercised (in shares)	(26,150)
Canceled (in shares)	(5,321)
Ending balance (in shares)	1,159,967	1,097,323
Exercisable at period end (in shares)	941,442
Weighted-Average Exercise Price per Share
Beginning balance (in dollars per share)	$ 32.70
Granted (in dollars per share)	61.39
Exercised (in dollars per share)	26.89
Canceled (in dollars per share)	69.37
Ending balance (in dollars per share)	35.00	$ 32.70
Exercisable (in dollars per share)	$ 27.17
Weighted-Average Remaining Contractual Life
Outstanding, weighted average remaining contractual life	4 years 8 months 15 days	4 years 9 months 18 days
Exercisable weighted average remaining contractual life	3 years 1 month 299 days
Aggregate Intrinsic Value
Beginning balance	$ 42,154
Granted	828
Exercised	1,132
Canceled	4
Ending balance	40,825	$ 42,154
Exercisable	$ 40,501