Consolidated Statements of Cash Flows - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Cash flows from operating activities:
Net income (loss)	$ 142.9	$ (315.6)	$ (999.6)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation and amortization	607.5	638.6	617.0
Impairments	0.8	362.8	1,133.5
(Gain) loss on disposition of assets	(1.5)	8.8	(1.9)
Loss on secured term loan receivable	0.0	0.0	52.9
Non-cash unit-based compensation	25.3	28.4	39.4
Utility credits, net of usage	(32.6)	0.0	0.0
Non-cash loss on derivatives recognized in net income (loss)	10.3	14.8	2.5
Gain on extinguishment of debt	0.0	(32.0)	0.0
Amortization of debt issuance costs and net discount of senior unsecured notes	5.2	4.6	4.9
Amortization of designated cash flow hedge	12.5	0.5	0.1
Payments to terminate interest rate swaps	(1.8)	(10.9)	0.0
Deferred income tax expense	24.6	142.1	6.9
Distribution of earnings from unconsolidated affiliates	0.0	1.6	16.5
(Income) loss from unconsolidated affiliates	11.5	(0.6)	16.8
Other operating activities	(2.2)	(0.8)	(2.3)
Changes in assets and liabilities:
Accounts receivable, accrued revenue, and other	(259.9)	(21.5)	337.1
Natural gas and NGLs inventory, prepaid expenses, and other	(13.6)	15.1	13.6
Accounts payable, accrued product purchases, and other accrued liabilities	328.3	(104.8)	(245.5)
Net cash provided by operating activities	857.3	731.1	991.9
Cash flows from investing activities:
Additions to property and equipment	(184.0)	(302.2)	(754.9)
Acquisition of assets	(56.7)	(32.3)	0.0
Proceeds from sale of property	4.8	17.6	14.3
Distribution from unconsolidated affiliates in excess of earnings	3.9	0.5	3.7
Other investing activities	0.6	(1.3)	(4.6)
Net cash used in investing activities	(231.4)	(317.7)	(741.5)
Cash flows from financing activities:
Proceeds from borrowings	1,234.5	1,650.0	3,310.0
Payments on borrowings	(1,469.5)	(1,786.0)	(2,971.4)
Distribution to members	(186.8)	(232.7)	(467.2)
Distributions to non-controlling interests	(130.8)	(121.2)	(220.5)
Redemption of Series B Preferred Units	(50.0)	0.0	0.0
Common unit repurchases	(40.1)	(1.2)	0.0
Contributions by non-controlling interests	3.2	52.6	97.5
Conversion of restricted units, net of units withheld for taxes	(2.0)	(4.7)	(7.8)
Debt financing costs	(0.3)	(7.7)	(10.0)
Other financing activities	2.5	(0.3)	(4.0)
Net cash used in financing activities	(639.3)	(451.2)	(273.4)
Net decrease in cash and cash equivalents	(13.4)	(37.8)	(23.0)
Cash and cash equivalents, beginning of period	39.6	77.4	100.4
Cash and cash equivalents, end of period	$ 26.2	$ 39.6	$ 77.4