Debt - Additional Information 7 (Detail) (USD $)				1 Months Ended		1 Months Ended
	Sep. 30, 2013	Dec. 31, 2012	Apr. 24, 2009	Sep. 28, 2012 5.625% Senior Notes [Member]	Sep. 30, 2013 5.625% Senior Notes [Member]	Jul. 13, 2012 5.75% Notes [Member]
Line of Credit Facility [Line Items]
Unsecured senior notes	$ 5,691,697,000	$ 5,440,073,000		$ 500,000,000		$ 800,000,000
Interest rate for senior notes				5.625%	5.625%	5.75%
Interest payable dates				October 1 and April 1		July 15 and January 15
Debt instrument, maturity date				Oct. 01, 2019		Jul. 15, 2020
Deferred financing fees			$ 7,700,000	$ 8,500,000		$ 14,000,000