Equity and Distributions, Accumulated Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Accumulated Other Comprehensive Income (Loss) [Abstract]
Beginning Balance	$ (219.2)	$ (241.6)
Other comprehensive income (loss) before reclassifications	(1.3)	30.8
Amounts reclassified from accumulated other comprehensive loss (income)	(48.0)	(52.4)
Total other comprehensive income (loss)	(49.3)	(21.6)
Ending Balance	(268.5)	(263.2)
Interest expense	240.6	239.1
Revenue	(5,005.3)	(7,472.5)
Operating costs and expenses	4,146.9	6,616.4
Total	(670.2)	(650.6)
Gains and Losses on Cash Flow Hedges [Member] | Interest rate derivatives [Member]
Accumulated Other Comprehensive Income (Loss) [Abstract]
Beginning Balance	(279.5)	(314.8)
Other comprehensive income (loss) before reclassifications	0.0	0.0
Amounts reclassified from accumulated other comprehensive loss (income)	9.2	8.7
Total other comprehensive income (loss)	9.2	8.7
Ending Balance	(270.3)	(306.1)
Gains and Losses on Cash Flow Hedges [Member] | Commodity derivatives [Member]
Accumulated Other Comprehensive Income (Loss) [Abstract]
Beginning Balance	56.6	69.9
Other comprehensive income (loss) before reclassifications	(1.2)	30.8
Amounts reclassified from accumulated other comprehensive loss (income)	(57.2)	(61.1)
Total other comprehensive income (loss)	(58.4)	(30.3)
Ending Balance	(1.8)	39.6
Other [Member]
Accumulated Other Comprehensive Income (Loss) [Abstract]
Beginning Balance	3.7	3.3
Other comprehensive income (loss) before reclassifications	(0.1)	0.0
Amounts reclassified from accumulated other comprehensive loss (income)	0.0	0.0
Total other comprehensive income (loss)	(0.1)	0.0
Ending Balance	3.6	3.3
Reclassification out of Accumulated Other Comprehensive Income [Member]
Accumulated Other Comprehensive Income (Loss) [Abstract]
Total	(48.0)	(52.4)
Reclassification out of Accumulated Other Comprehensive Income [Member] | Gains and Losses on Cash Flow Hedges [Member] | Interest rate derivatives [Member]
Accumulated Other Comprehensive Income (Loss) [Abstract]
Interest expense	9.2	8.7
Reclassification out of Accumulated Other Comprehensive Income [Member] | Gains and Losses on Cash Flow Hedges [Member] | Commodity derivatives [Member]
Accumulated Other Comprehensive Income (Loss) [Abstract]
Revenue	(58.8)	(61.1)
Operating costs and expenses	$ 1.6	$ 0.0