Property, Plant and Equipment, Other (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Property, Plant and Equipment [Line Items]
Capital expenditures			$ 2,443.9	$ 2,630.5
Loss due to Pascagoula fire	$ 0.0	$ 0.0	7.1	$ 0.0
Insurance Matters [Abstract]
Insurance deductible per incident	55.0		$ 55.0
Minimum business interruption period			60 days
Pascagoula Natural Gas Processing Facility [Member]
Property, Plant and Equipment [Line Items]
Undivided ownership interest acquired			60.00%
Capital expenditures			$ 35.0
Loss due to Pascagoula fire			7.1
Fire response expenses	$ 7.1		$ 7.1