Employee Benefit Plans - Components of Net Periodic Pension Cost for Defined Benefit Pension Plan and Retirement Plan (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Compensation and Retirement Disclosure [Abstract]
Service cost	$ 843	$ 749	$ 523
Interest cost	1,160	1,167	1,043
Expected return on plan assets	(1,222)	(1,060)	(1,053)
Amortization of actuarial losses	1,093	1,147	430
Net periodic pension cost	$ 1,874	$ 2,003	$ 943