Supplemental Cash Flow Disclosures - Supplemental Cash Flow Reconciliation (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Supplemental Cash Flow Information [Line Items]
Interest expense, net of interest capitalized	$ 515.7	$ 450.3	$ 1,574.3	$ 1,448.3
Adjustments to reconcile to cash paid for interest:
Net change in accruals			(138.7)	(201.8)
Amortization of deferred finance charges			(66.5)	(54.0)
Net amortization of discounts and premiums			(166.2)	(122.2)
Amortization of accumulated other comprehensive loss			(21.2)	(60.6)
Rollover of PIK interest to principal			(1.0)	(1.1)
Change in fair value of derivative instruments			(10.9)	62.4
Cash paid for interest			1,169.8	1,071.0
Cash payments/(refunds) of income taxes, net			$ 9.1	$ (2.4)