Stock-Based Compensation - Summary of Stock Option Activity (Detail) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2016 USD ($) $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Number of Shares, Outstanding, Beginning Balance (in shares) | shares	118,879
Number of Shares, Exercised (in shares) | shares	(15,333)
Number of Shares, Outstanding, Ending Balance (in shares) | shares	103,546
Number of Shares, Exercisable, Ending Balance (in shares) | shares	103,546
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract]
Weighted Average Exercise Price, Outstanding, Beginning Balance (in dollars per share)	$ 16.23
Weighted Average Exercise Price, Exercised (in dollars per share)	22.87
Weighted Average Exercise Price, Outstanding, Ending Balance (in dollars per share)	15.24
Weighted Average Exercise Price, Exercisable, Ending Balance (in dollars per share)	$ 15.24
Weighted-average remaining contractual life, options exercisable	3 years 5 months 12 days
Aggregate intrinsic value, outstanding | $	$ 1,388
Aggregate intrinsic value, exercisable | $	$ 1,388
Minimum [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Roll Forward]
Option Price Per Share, Outstanding, Beginning Balance (in dollars per share)	$ 2.89
Option Price Per Share, Exercised (in dollars per share)	22.17
Option Price Per Share, Outstanding, Ending Balance (in dollars per share)	2.89
Option Price Per Share, Exercisable, Ending Balance (in dollars per share)	2.89
Maximum [Member]
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Roll Forward]
Option Price Per Share, Outstanding, Beginning Balance (in dollars per share)	24.65
Option Price Per Share, Exercised (in dollars per share)	24.65
Option Price Per Share, Outstanding, Ending Balance (in dollars per share)	22.17
Option Price Per Share, Exercisable, Ending Balance (in dollars per share)	$ 22.17