Derivative Instruments and Hedging Activities (Fair Value of Derivative Instruments Outstanding) (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2012	Dec. 31, 2011
Fair Value Hedge Liabilities	$ 0
Derivative Instruments Not Designated as Hedging Instruments, Asset, at Fair Value	8.3	10.4
Fair Value Hedge Assets	97.0
Derivative Asset Designated as Hedging Instrument, Fair Value	105.3	159.2
Derivative Liability Designated as Hedging Instrument, Fair Value	12.5	16.5
Derivative Instruments Not Designated as Hedging Instruments, Liability, at Fair Value	12.5	16.5
Interest-Rate Swap Agreements [Member] | Other Assets [Member]
Derivative Instruments Not Designated as Hedging Instruments, Asset, at Fair Value	6.2	6.0
Fair Value Hedge Assets	97.0	147.6
Interest-Rate Swap Agreements [Member] | Other Liabilities [Member]
Fair Value Hedge Liabilities	0	0
Derivative Instruments Not Designated as Hedging Instruments, Liability, at Fair Value	6.2	6.0
Foreign Exchange Forward Contracts [Member] | Accounts Payable [Member]
Fair Value Hedge Liabilities	0
Derivative Instruments Not Designated as Hedging Instruments, Liability, at Fair Value	6.3	10.5
Foreign Exchange Forward Contracts [Member] | Prepaid Expenses and Other [Member]
Derivative Instruments Not Designated as Hedging Instruments, Asset, at Fair Value	2.1	4.4
Fair Value Hedge Assets	$ 0