Derivative Instruments and Hedging Activities (Narrative) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Jan. 31, 2013	Dec. 31, 2012
Minimum Cumulative Rate Percentage of Fair Value Derivative to Qualify as Highly Effective Derivative Instrument	85.00%
Maximum Cumulative Rate Percentage of Fair Value Derivative to Qualify as Highly Effective Derivative Instrument	125.00%
Percentage of long-term, fixed-rate borrowings converted to variable interest rate instruments using interest rate swaps	7.00%			62.00%
Total exposure to floating rate interest rates	31.00%			69.00%
Notional Amount Related to Discontinuation of Interest Rate Fair Value Hedge		$ 350.0	$ 1,000.0
Deferred Gain (Loss) on Discontinuation of Interest Rate Fair Value Hedge		46.1
Interest Rate Swap Termination Fee		2.5
Notional amount of interest-rate swap agreements designated as fair value hedges of fixed rate debt	125
Change in fair market value of interest-rate swap agreements	(0.7)	(4.5)
Notional amount of interest-rate swap agreements not designated as fair value hedges of fixed rate debt	250
Gain (Loss) on Interest Rate Fair Value Hedge Ineffectiveness	0	0
Notional amounts of foreign currency exchange contracts	238
Derivative Instruments, Gain Recognized in Other Comprehensive Income (Loss), Effective Portion	0	(0.3)
Intercompany Loans [Member]
Gain (Loss) on Foreign Currency Derivative Instruments Not Designated as Hedging Instruments	(3.0)	3.4
Gain (loss) due to the effect of foreign currency exchange rates on intercompany loans	3.1	(2.9)
January 2013 Interest-Rate Swap Termination [Member]
Deferred Gain (Loss) on Discontinuation of Interest Rate Fair Value Hedge	85.2		90.4
Interest Rate Swap Termination Fee	2.3
Amortization of Interest Rate Swap Gains	5.2
March 2012 Interest-Rate Swap Termination [Member]
Deferred Gain (Loss) on Discontinuation of Interest Rate Fair Value Hedge	40.2
Amortization of Interest Rate Swap Gains	1.5
Short-term Debt [Member] | January 2013 Interest-Rate Swap Termination [Member]
Deferred Gain (Loss) on Discontinuation of Interest Rate Fair Value Hedge	10.3
Long-term Debt [Member] | January 2013 Interest-Rate Swap Termination [Member]
Deferred Gain (Loss) on Discontinuation of Interest Rate Fair Value Hedge	$ 74.9