Leases - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Leases [Abstract]
Operating lease expiration year	2021
Rent expense	$ 7.5	$ 7.2	$ 5.9
Rent expense associated with related party lease agreements	1.7	1.7	1.8
Non-cancelable payments due to related parties, year one	1.7
Non-cancelable payments due to related parties, year two	1.7
Non-cancelable payments due to related parties, year three	1.7
Non-cancelable payments due to related parties, year four	$ 1.7