Equity and Distributions, Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Accumulated Other Comprehensive Income (Loss) [Abstract]
Beginning Balance			$ (280.0)	$ (219.2)
Other comprehensive income (loss) before reclassifications			170.6	(84.4)
Amounts reclassified from accumulated other comprehensive loss (income)			(19.3)	(3.4)
Total other comprehensive income (loss)	$ (12.5)	$ (38.5)	151.3	(87.8)
Ending Balance	(128.7)	(307.0)	(128.7)	(307.0)
Interest expense	245.8	244.1	495.1	484.7
Revenue	(6,607.6)	(5,617.8)	(13,928.0)	(10,623.1)
Operating costs and expenses	5,730.2	4,822.2	12,063.4	8,969.1
Total	(666.0)	(570.0)	(1,437.0)	(1,240.2)
Gains and Losses on Cash Flow Hedges [Member] | Interest Rate Derivatives [Member]
Accumulated Other Comprehensive Income (Loss) [Abstract]
Beginning Balance			(199.8)	(279.5)
Other comprehensive income (loss) before reclassifications			(4.5)	(9.4)
Amounts reclassified from accumulated other comprehensive loss (income)			19.6	18.4
Total other comprehensive income (loss)			15.1	9.0
Ending Balance	(184.7)	(270.5)	(184.7)	(270.5)
Gains and Losses on Cash Flow Hedges [Member] | Commodity Derivatives [Member]
Accumulated Other Comprehensive Income (Loss) [Abstract]
Beginning Balance			(83.8)	56.6
Other comprehensive income (loss) before reclassifications			175.2	(74.9)
Amounts reclassified from accumulated other comprehensive loss (income)			(38.9)	(21.8)
Total other comprehensive income (loss)			136.3	(96.7)
Ending Balance	52.5	(40.1)	52.5	(40.1)
Other [Member]
Accumulated Other Comprehensive Income (Loss) [Abstract]
Beginning Balance			3.6	3.7
Other comprehensive income (loss) before reclassifications			(0.1)	(0.1)
Amounts reclassified from accumulated other comprehensive loss (income)			0.0	0.0
Total other comprehensive income (loss)			(0.1)	(0.1)
Ending Balance	3.5	3.6	3.5	3.6
Reclassification out of Accumulated Other Comprehensive Income (Loss) [Member]
Accumulated Other Comprehensive Income (Loss) [Abstract]
Total	(36.0)	44.6	(19.3)	(3.4)
Reclassification out of Accumulated Other Comprehensive Income (Loss) [Member] | Gains and Losses on Cash Flow Hedges [Member] | Interest Rate Derivatives [Member]
Accumulated Other Comprehensive Income (Loss) [Abstract]
Interest expense	10.0	9.2	19.6	18.4
Reclassification out of Accumulated Other Comprehensive Income (Loss) [Member] | Gains and Losses on Cash Flow Hedges [Member] | Commodity Derivatives [Member]
Accumulated Other Comprehensive Income (Loss) [Abstract]
Revenue	(46.0)	34.2	(38.5)	(24.6)
Operating costs and expenses	$ 0.0	$ 1.2	$ (0.4)	$ 2.8