Supplemental Cash Flow Information - Supplemental Cash Flow Reconciliation (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Supplemental Cash Flow Information [Abstract]
Interest expense, net of interest capitalized	$ 563.0	$ 515.8	$ 1,677.7	$ 1,574.3
Adjustments to reconcile to cash paid for interest:
Net change in accurals			(142.4)	(138.7)
Amortization of deferred finance charges			(41.6)	(66.5)
Net amortization of discounts and premiums			(231.4)	(166.2)
Amortization of accumulated other comprehensive loss			(4.5)	(21.2)
Rollover of PIK interest to principal			(1.2)	(1.0)
Change in fair value of derivative instruments			100.6	(10.9)
Cash paid for interest			1,357.2	1,169.8
Cash payments for income taxes, net			$ 25.2	$ 9.1