Fair Value (Fair Value Assets and Liabilities Measured at Fair Value on a Recurring Basis) (Details) (USD $) In Millions, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Total Assets	$ 111.8	$ 161.0
Fair Value Measured On Recurring Basis Liabilities	11.7	16.5
Available-for-sale Securities [Member]
Available-for-sale securities	1.9	1.8
Interest-Rate Swap Agreements [Member]
Derivative Assets	104.2	153.6
Derivative Liabilities	3.8	6.0
Foreign Exchange Forward Contracts [Member]
Derivative Assets	5.7	5.6
Derivative Liabilities	7.9	10.5
Level 1 [Member]
Total Assets	1.9	1.8
Fair Value Measured On Recurring Basis Liabilities	0	0
Level 1 [Member] | Available-for-sale Securities [Member]
Available-for-sale securities	1.9	1.8
Level 1 [Member] | Interest-Rate Swap Agreements [Member]
Derivative Assets	0	0
Derivative Liabilities	0	0
Level 1 [Member] | Foreign Exchange Forward Contracts [Member]
Derivative Assets	0	0
Derivative Liabilities	0	0
Level 2 [Member]
Total Assets	109.9	159.2
Fair Value Measured On Recurring Basis Liabilities	11.7	16.5
Level 2 [Member] | Available-for-sale Securities [Member]
Available-for-sale securities	0	0
Level 2 [Member] | Interest-Rate Swap Agreements [Member]
Derivative Assets	104.2	153.6
Derivative Liabilities	3.8	6.0
Level 2 [Member] | Foreign Exchange Forward Contracts [Member]
Derivative Assets	5.7	5.6
Derivative Liabilities	$ 7.9	$ 10.5