Stock-Based Compensation - Summary of Weighted Average Grant-Date Fair Value Granted and Total Fair Value of Restricted Shares and Restricted Stock Units Vested (Detail) (Restricted Shares [Member], Restricted Stock Units [Member], USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Restricted Shares [Member] | Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Granted, Shares	706	420	339
Weighted average grant-date fair value	$ 15.25	$ 15.21	$ 18.68
Fair value of vested	$ 366	$ 3,845	$ 4,392