Stock-Based Compensation - Summary of Options Including Non-Plan Stock Options (Detail) - Stock Incentive Plan 2013 - $ / shares	3 Months Ended
	Mar. 31, 2017	Dec. 31, 2016
Shares
Outstanding at end of period (in shares)	2,096,535
Employee Stock Option
Shares
Outstanding at beginning of period (in shares)	1,547,980
Granted (in shares)	45,134
Exercised (in shares)	(117,612)
Forfeited (in shares)	(750)
Outstanding at end of period (in shares)	1,474,752
Weighted- Average Exercise Price
Outstanding at beginning of period (in dollars per share)	$ 17.83
Granted (in dollars per share)	47.05
Exercised (in dollars per share)	15.47
Forfeited (in dollars per share)	15.83
Outstanding at end of period (in dollars per share)	$ 18.91
Nonvested at end of period (in shares)	424,459	704,421
Nonvested at end of period (in dollars per share)	$ 23.64	$ 19.08
Exercisable at end of period (in shares)	1,050,293
Exercisable at end of period (in dollars per share)	$ 17.00
Weighted-average fair value of options granted (in shares)	$ 11.50