Debt and Credit Facilities (Short-Term Borrowings and Current Maturities of Long-Term Debt) (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2013	Dec. 31, 2012
Short-term borrowings and current maturities of long-term debt	$ 965.1	$ 963.7
Debentures With Put Feature [Member]
Short-term borrowings and current maturities of long-term debt	343.0	343.0
6.000% Senior Notes Due 2013 [Member]
Short-term borrowings and current maturities of long-term debt	600.0	600.0
Current Maturities Of Long Term Debt [Member]
Short-term borrowings and current maturities of long-term debt	9.0	10.8
Other Short Term Borrowings [Member]
Short-term borrowings and current maturities of long-term debt	$ 13.1	$ 9.9