Employee Benefit Plans - Schedule of Changes in Components of Accumulated Other Comprehensive Loss (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Compensation and Retirement Disclosure [Abstract]
Accumulated Other Comprehensive Income (Loss) Before Tax - Beginning Balance	$ (13,058)
Net actuarial gain	17,566	621	(9,504)
Settlement gain	42	792	1,204
Actuarial (gains)/losses	2,037	2,718	1,803
Prior service costs/(credits)	(1,555)	(1,555)	(1,555)
Accumulated Other Comprehensive Income (Loss) Before Tax - Ending Balance	5,032	(13,058)
Balance at January 1, 2013	5,128
Net actuarial gain	(6,811)	(242)	(3,709)
Settlement gain	(17)	(309)	(470)
Actuarial (gains)/losses	(790)	(1,062)	(704)
Prior service costs/(credits)	604
Balance at December 31, 2013	(1,886)	5,128
Balance at January 1, 2013	(7,930)
Net actuarial gain	10,755	379	(5,795)
Settlement gain	25	483	734
Actuarial (gains)/losses	1,247	1,656	1,099
Prior service costs/(credits)	(951)	(948)	(948)
Balance at December 31, 2013	$ 3,146	$ (7,930)