Debt and Credit Facilities (Narrative) (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended	6 Months Ended
	Oct. 31, 2014	Dec. 31, 2014	Jun. 30, 2015	Jun. 30, 2014	Feb. 28, 2015	Sep. 30, 2014
Short-term borrowings and current maturities of long-term debt		$ 482.7	$ 659.7
Repayments of Long-term Debt			23.7	$ 7.8
Line of credit facility, amount outstanding			2,000.0
Debt Instrument, Fair Value Disclosure		4,700.0
Five Year Revolving Credit Facility [Member]
Line of credit facility, amount outstanding			1,000.0
Debentures With Put Feature [Member]
Short-term borrowings and current maturities of long-term debt		343.0	$ 343.0
Debt instrument, maturity date range, start			Jan. 01, 2027
Debt instrument, maturity date range, end			Dec. 31, 2028
Debentures with put option available to be exercised					$ 37.2
Four Point Seven Five Percent Senior Notes Due Two Thousand Fifteen [Member]
Debt instrument, interest rate, stated percentage						4.75%
Repayments of Long-term Debt	$ 300.0
Senior Notes Issued in 2014 [Member]
Debt Instrument, face amount		1,100.0
Two Point Six Two Five Percent Senior Notes Due Two Thousand Twenty [Member]
Debt Instrument, face amount		$ 300.0
Debt instrument, interest rate, stated percentage		2.625%
Three Point Five Five Percent Senior Notes due 2024 [Member]
Debt Instrument, face amount		$ 500.0
Debt instrument, interest rate, stated percentage		3.55%
Four Point Six Five Percent Senior Notes due Twenty Forty Four [Member]
Debt Instrument, face amount		$ 300.0
Debt instrument, interest rate, stated percentage		4.65%
Five Point Five Zero Percent Senior Notes Due Two Thousand Fifteen [Member]
Debt instrument, interest rate, stated percentage						5.50%
Repayments of Long-term Debt	$ 200.0
Redemption in Fourth Quarter Twenty Fourteen [Member]
Redemption Premium		$ 10.2