Other Assets (Additional Information) (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Other Assets [Abstract]
Amortization expense on intangible assets, included in other assets	$ 8,634	$ 8,717	$ 21,392	$ 20,135