Shared-Based Compensation - Reconciliation of Option Activity (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands		9 Months Ended
		Sep. 30, 2016	Sep. 30, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Number of options, Outstanding, Beginning Balance		1,034
Number of Options, Granted		167	54,600
Number of Options, Exercised		(242)
Number of Options, Forfeited or expired		(33)
Number of Options, Outstanding, Ending Balance		926
Number of Options, Options Exercisable		714
Weighted-Average Exercise Price, Outstanding, Beginning Balance		$ 12.09
Weighted-Average Exercise Price, Granted		11.31
Weighted-Average Exercise Price, Exercised		10.54
Weighted-Average Exercise Price, Forfeited or expired		17.38
Weighted-Average Exercise Price, Outstanding, Ending Balance		12.16
Weighted-Average Exercise Price, Options exercisable		$ 11.54
Weighted-Average Remaining Contractual Term, Outstanding, Ending Balance		6 years 1 month 6 days
Weighted- Average Remaining Contractual Term, Options exercisable		5 years 2 months 12 days
Aggregate Intrinsic Value, Outstanding, Ending Balance	[1]	$ 6,092
Aggregate Intrinsic Value, Options exercisable	[1]	$ 1,086

[1] The intrinsic value is the amount by which the market price of our stock was greater than the exercise price of any individual option grant at September 30, 2016