Stock Incentive Plans - Summary of Stock Options Activity (Detail) - Stock Options [Member] $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2016 USD ($) $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Outstanding beginning balance, Number of Options | shares	360,100
Options granted, Number of Options | shares	10,000
Options exercised, Number of Options | shares	(4,400)
Options cancelled, Number of Options | shares	(62,500)
Outstanding ending balance, Number of Options | shares	303,200
Number of Options, exercisable stock options | shares	206,950
Outstanding beginning balance, Weighted Average Exercise Price | $ / shares	$ 17.35
Options granted, Weighted Average Exercise Price | $ / shares	39.80
Options exercised, Weighted Average Exercise Price | $ / shares	14.32
Options canceled, Weighted Average Exercise Price | $ / shares	18.56
Outstanding ending balance, Weighted Average Exercise Price | $ / shares	17.89
Weighted Average Exercise Price, exercisable stock options | $ / shares	$ 15.44
Weighted Average Remaining Contractual Term of outstanding stock options	4 years 6 months 11 days
Weighted Average Remaining Contractual Term of exercisable stock options	3 years 10 months 10 days
Aggregate Intrinsic Value, outstanding stock option | $	$ 14,012
Aggregate Intrinsic Value, exercisable stock option | $	$ 10,069