STATEMENTS OF CONSOLIDATED CASH FLOWS - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Operating activities:
Net income	$ 2,553.0	$ 2,558.4	$ 2,833.5
Reconciliation of net income to net cash flows provided by operating activities:
Depreciation, amortization and accretion	1,552.0	1,516.0	1,360.5
Asset impairment charges	53.5	162.6	34.0
Equity in income of unconsolidated affiliates	(362.0)	(373.6)	(259.5)
Distributions received on earnings from unconsolidated affiliates	380.5	462.1	375.1
Net losses (gains) attributable to asset sales and insurance recoveries	(2.5)	15.6	(102.1)
Gains on early extinguishment of debt	0.0	(1.6)	0.0
Deferred income tax expense (benefit)	6.6	(20.6)	6.1
Change in fair market value of derivative instruments	45.0	(18.4)	30.6
Change in fair market value of Liquidity Option Agreement	24.5	25.4	0.0
Net effect of changes in operating accounts	(180.9)	(323.3)	(108.2)
Other operating activities	(2.9)	(0.2)	(7.8)
Net cash flows provided by operating activities	4,066.8	4,002.4	4,162.2
Investing activities:
Capital expenditures	(3,025.1)	(3,830.7)	(2,892.9)
Contributions in aid of construction costs	41.0	19.1	28.9
Decrease (increase) in restricted cash	(338.6)	(15.9)	65.6
Cash used for business combinations, net of cash received	(1,000.0)	(1,056.5)	(2,416.8)
Investments in unconsolidated affiliates	(138.8)	(162.6)	(722.4)
Distributions received for return of capital from unconsolidated affiliates	71.0	0.0	0.0
Proceeds from asset sales and insurance recoveries	46.5	1,608.6	145.3
Other investing activities	(0.4)	(3.8)	(5.6)
Cash used in investing activities	(4,344.4)	(3,441.8)	(5,797.9)
Financing activities:
Borrowings under debt agreements	62,813.9	21,081.1	18,361.1
Repayments of debt	(61,672.6)	(19,867.2)	(14,341.1)
Debt issuance costs	(10.6)	(24.0)	(41.2)
Monetization of interest rate derivative instruments	6.1	0.0	27.6
Cash distributions paid to limited partners	(3,300.5)	(2,943.7)	(2,638.1)
Cash payments made in connection with distribution equivalent rights	(11.7)	(7.7)	(3.7)
Cash distributions paid to noncontrolling interests	(47.4)	(48.0)	(48.6)
Cash contributions from noncontrolling interests	20.4	54.0	4.0
Net cash proceeds from the issuance of common units	2,542.8	1,188.6	388.8
Other financing activities	(18.7)	(49.1)	(55.6)
Cash provided by (used in) financing activities	321.7	(616.0)	1,653.2
Net change in cash and cash equivalents	44.1	(55.4)	17.5
Cash and cash equivalents, January 1	19.0	74.4	56.9
Cash and cash equivalents, December 31	$ 63.1	$ 19.0	$ 74.4