Stock Based Compensation - Reconciliation of Option Activity (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Number of options, Outstanding, Beginning Balance	1,034,000
Number of Options, Granted	167,000	54,600	108,620
Number of Options, Exercised	(270,000)
Number of Options, Forfeited or expired	(34,000)
Number of Options, Outstanding, Ending Balance	897,000	1,034,000
Number of Options, Options Exercisable	686,000
Weighted-Average Exercise Price, Outstanding, Beginning Balance	$ 12.09
Weighted-Average Exercise Price, Granted	11.31
Weighted-Average Exercise Price, Exercised	10.49
Weighted-Average Exercise Price, Forfeited or expired	17.52
Weighted-Average Exercise Price, Outstanding, Ending Balance	12.22	$ 12.09
Weighted-Average Exercise Price, Options exercisable	$ 11.59
Weighted-Average Remaining Contractual Term, Outstanding	5 years 10 months 24 days
Weighted- Average Remaining Contractual Term, Options exercisable	4 years 10 months 24 days
Aggregate Intrinsic Value, Outstanding	$ 6,479
Aggregate Intrinsic Value, Options exercisable	$ 5,267