Share-Based Compensation and Other Benefit Plans (Summary of Activity of Service Based Restricted Shares Under LTIP) (Detail) (Service-based restricted stock, USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Service-based restricted stock
Number of Shares
Outstanding at the beginning of the year (in shares)	286,306	229,722	264,657
Granted (in shares)	293,732	135,223	119,964
Vested (in shares)	(197,014)	(68,683)	(109,638)
Forfeited or expired (in shares)	(7,211)	(9,956)	(45,261)
Outstanding at the end of the year (in shares)	375,813	286,306	229,722
Weighted- Average Grant Date Fair Value
Outstanding at the beginning of the year (in dollars per share)	$ 11.83	$ 12.40	$ 10.78
Granted (in dollars per share)	$ 15.68	$ 11.30	$ 13.34
Vested (in dollars per share)	$ 10.07	$ 11.47	$ 11.04
Forfeited or expired (in dollars per share)	$ 13.38	$ 11.95	$ 13.12
Outstanding at the end of the year (in dollars per share)	$ 13.71	$ 11.83	$ 12.40