Benefit Plans - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Defined Benefit Plan Disclosure [Line Items]
Maximum matching contribution	4.00%
Employer profit sharing and matching contribution expense	$ 3.2	$ 3.0	$ 3.2