Financing Arrangements and Debt (Details) $ in Millions	3 Months Ended
	Mar. 31, 2016 USD ($)
Line of Credit Facility [Line Items]
Capital lease duration	25 years
Capital lease payment duration	15 years
Capital lease obligations, current	$ 19.1
Capital lease obligations, noncurrent	206.7
Committed Credit Facility [Member]
Line of Credit Facility [Line Items]
Credit facility maximum borrowing capacity	$ 2,000.0
Credit facility, maturity date	Jun. 01, 2017
Credit facility interest rate above LIBOR	1.45%
Line of credit facility fee	0.30%
Amount outstanding	$ 925.0
Uncommitted Credit Facilities [Member]
Line of Credit Facility [Line Items]
Amount outstanding	46.0
Current borrowing capacity	82.0
Letter of Credit [Member]
Line of Credit Facility [Line Items]
Amount outstanding	$ 88.0