Changes in Intangible Assets Other Than Goodwill (Detail) (USD $)	3 Months Ended	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Indefinite-Lived Intangible Assets
Indefinite-Lived Intangible Assets, Beginning Balance		$ 1,625,415,000	$ 160,418,000
Purchase price allocation adjustments
Acquisitions		22,253,000	1,466,530,000
Impairments	(14,700,000)	(14,706,000)
Dispositions		(30,589,000)	(1,533,000)
Indefinite-Lived Intangible Assets, Ending Balance	1,602,373,000	1,602,373,000	1,625,415,000	160,418,000
Definite-Lived Intangible Assets
Definite-Lived Intangible Assets, Beginning Balance		390,509,000	552,000
Purchase price allocation adjustments		(1,027,000)
Acquisitions		376,000	428,408,000
Impairments		(12,435,000)
Dispositions		(6,880,000)	(83,000)
Amortization		(112,240,000)	(38,368,000)	0
Definite-Lived Intangible Assets, Ending Balance	258,303,000	258,303,000	390,509,000	552,000
Intangible Assets, Net
Intangible Assets Total, Beginning Balance		2,015,924,000	160,970,000
Purchase price allocation adjustments		(1,027,000)
Acquisitions	22,629,000	22,629,000	1,894,938,000
Impairments		(27,141,000)
Dispositions		(37,469,000)	(1,616,000)
Amortization		(112,240,000)	(38,368,000)	0
Intangible Assets Total, Ending Balance	$ 1,860,676,000	$ 1,860,676,000	$ 2,015,924,000	$ 160,970,000