STATEMENTS OF CONSOLIDATED CASH FLOWS - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Operating activities:
Net income	$ 2,558.4	$ 2,833.5	$ 2,607.1
Reconciliation of net income to net cash flows provided by operating activities:
Depreciation, amortization and accretion	1,516.0	1,360.5	1,217.6
Non-cash asset impairment charges	162.6	34.0	92.6
Equity in income of unconsolidated affiliates	(373.6)	(259.5)	(167.3)
Distributions received from unconsolidated affiliates	462.1	375.1	251.6
Net losses (gains) attributable to asset sales and insurance recoveries	15.6	(102.1)	(83.3)
Gains on early extinguishment of debt	(1.6)	0.0	0.0
Deferred income tax expense (benefit)	(20.6)	6.1	37.9
Changes in fair value of Liquidity Option Agreement	25.4	0.0	0.0
Changes in fair market value of derivative instruments	(18.4)	30.6	1.4
Net effect of changes in operating accounts	(323.3)	(108.2)	(97.6)
Other operating activities	(0.2)	(7.8)	5.5
Net cash flows provided by operating activities	4,002.4	4,162.2	3,865.5
Investing activities:
Capital expenditures	(3,830.7)	(2,892.9)	(3,408.2)
Contributions in aid of construction costs	19.1	28.9	26.0
Decrease (increase) in restricted cash	(15.9)	65.6	(61.3)
Cash used for business combinations, net of cash received	(1,056.5)	(2,416.8)	0.0
Investments in unconsolidated affiliates	(162.6)	(722.4)	(1,094.1)
Proceeds from asset sales and insurance recoveries	1,608.6	145.3	280.6
Other investing activities	(3.8)	(5.6)	(0.5)
Cash used in investing activities	(3,441.8)	(5,797.9)	(4,257.5)
Financing activities:
Borrowings under debt agreements	21,081.1	18,361.1	13,852.8
Repayments of debt	(19,867.2)	(14,341.1)	(12,680.6)
Debt issuance costs	(24.0)	(41.2)	(23.7)
Monetization of interest rate derivative instruments	0.0	27.6	(168.8)
Cash distributions paid to limited partners	(2,943.7)	(2,638.1)	(2,400.3)
Cash payments made in connection with distribution equivalent rights	(7.7)	(3.7)	0.0
Cash distributions paid to noncontrolling interests	(48.0)	(48.6)	(8.9)
Cash contributions from noncontrolling interests	54.0	4.0	115.4
Net cash proceeds from the issuance of common units	1,188.6	388.8	1,792.0
Other financing activities	(49.1)	(55.6)	(45.1)
Cash provided by (used in) financing activities	(616.0)	1,653.2	432.8
Net change in cash and cash equivalents	(55.4)	17.5	40.8
Cash and cash equivalents, January 1	74.4	56.9	16.1
Cash and cash equivalents, December 31	$ 19.0	$ 74.4	$ 56.9