Supplemental Cash Flow Information - Supplemental Cash Flow Reconciliation (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Supplemental Cash Flow Information [Abstract]
Amount reclassified from AOCL to interest expense	$ 2,253.0	$ 2,100.3	$ 2,121.7
Adjustments to reconcile to cash paid for interest:
Net change in accrued interest	(125.4)	(13.1)	(11.9)
Amortization of deferred finance charges	(51.2)	(88.5)	(70.3)
Net amortization of discounts and premiums	(308.9)	(226.3)	(157.2)
Reclassification of accumulated other comprehensive loss	0	0	(183.2)
Amortization of other comprehensive loss	(4.7)	(29.1)	(83.3)
Rollover of PIK interest to principal	(1.2)	(1.0)	(1.1)
Change in fair value of derivative instruments	137.6	29.6	70.3
Cash paid for interest	$ 1,899.2	$ 1,771.9	$ 1,685.0