Goodwill and Intangible Assets, Net - Summary of Intangible Assets Acquired in Business Combinations (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Goodwill And Intangible Assets Disclosure [Abstract]
Intangible assets with definite lives	$ 33,707	$ 21,382
Less: accumulated amortization	(13,000)	(13,492)
Intangible assets with definite lives, net	20,707	7,890
Intangible assets with indefinite lives	30,300	30,300
Intangible assets, net	$ 51,007	$ 38,190