Goodwill and Other Intangible Assets - Components of Goodwill and Other Intangible Assets (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013	Sep. 30, 2013	Dec. 31, 2012
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill	$ 343,776	$ 345,453	$ 350,619	$ 364,328
Other intangible assets (net of accumulated amortization)	12,478	18,424
Goodwill and other intangible assets, Total	$ 356,254	$ 363,877