Consolidated Statement of Changes in Members' Equity - USD ($) $ in Millions		Total		Common Units	Accumulated Other Comprehensive Loss	Non-Controlling Interest	Redeemable Non-Controlling Interest (Temporary Equity)
Member equity, beginning balance at Dec. 31, 2020		$ 3,213.0		$ 1,508.8	$ (15.3)	$ 1,719.5
Units outstanding, beginning balance (in shares) at Dec. 31, 2020				489,400,000
Increase (Decrease) in Members' Equity
Conversion of unit-based awards for common units, net of units withheld for taxes		(1.2)		$ (1.2)
Conversion of unit-based awards for common units, net of units withheld for taxes (in shares)				700,000
Unit-based compensation		6.5		$ 6.5
Contributions from non-controlling interests		0.9				0.9
Distributions		(72.9)		(47.1)		(25.8)	$ (0.2)
Unrealized gain on designated cash flow hedge	[1]	3.6			3.6
Fair value adjustment related to redeemable non-controlling interest		(0.1)		(0.1)			0.2
Net income (loss)		12.6		(12.7)		25.3
Member equity, end balance at Mar. 31, 2021		3,162.4		$ 1,454.2	(11.7)	1,719.9
Units outstanding, end balance (in shares) at Mar. 31, 2021				490,100,000
Redeemable noncontrolling interest, beginning balance at Dec. 31, 2020							0.0
Temporary Equity [Abstract]
Distributions		(72.9)		$ (47.1)		(25.8)	(0.2)
Fair value adjustment related to redeemable non-controlling interest		(0.1)		(0.1)			0.2
Redeemable noncontrolling interest, ending balance at Mar. 31, 2021							0.0
Member equity, beginning balance at Dec. 31, 2020		3,213.0		$ 1,508.8	(15.3)	1,719.5
Units outstanding, beginning balance (in shares) at Dec. 31, 2020				489,400,000
Increase (Decrease) in Members' Equity
Unrealized gain on designated cash flow hedge	[2]	11.1
Common units repurchased		$ (14.5)
Common units repurchased (in shares)		(2,394,296)
Member equity, end balance at Sep. 30, 2021		$ 3,055.2		$ 1,338.8	(4.2)	1,720.6
Units outstanding, end balance (in shares) at Sep. 30, 2021				488,000,000.0
Redeemable noncontrolling interest, beginning balance at Dec. 31, 2020							0.0
Redeemable noncontrolling interest, ending balance at Sep. 30, 2021							0.0
Member equity, beginning balance at Mar. 31, 2021		3,162.4		$ 1,454.2	(11.7)	1,719.9
Units outstanding, beginning balance (in shares) at Mar. 31, 2021				490,100,000
Increase (Decrease) in Members' Equity
Conversion of unit-based awards for common units, net of units withheld for taxes		(0.2)		$ (0.2)
Conversion of unit-based awards for common units, net of units withheld for taxes (in shares)				100,000
Unit-based compensation		6.4		$ 6.4
Contributions from non-controlling interests		1.0				1.0
Distributions		(82.7)		(46.7)		(36.0)
Unrealized gain on designated cash flow hedge	[3]	3.7			3.7
Common units repurchased		(2.0)		$ (2.0)
Common units repurchased (in shares)				(300,000)
Net income (loss)		9.4		$ (21.6)		31.0
Member equity, end balance at Jun. 30, 2021		3,098.0		$ 1,390.1	(8.0)	1,715.9
Units outstanding, end balance (in shares) at Jun. 30, 2021				489,900,000
Redeemable noncontrolling interest, beginning balance at Mar. 31, 2021							0.0
Temporary Equity [Abstract]
Distributions		(82.7)		$ (46.7)		(36.0)
Redeemable noncontrolling interest, ending balance at Jun. 30, 2021							0.0
Increase (Decrease) in Members' Equity
Conversion of unit-based awards for common units, net of units withheld for taxes		(0.5)		$ (0.5)
Conversion of unit-based awards for common units, net of units withheld for taxes (in shares)				200,000
Unit-based compensation		6.4		$ 6.4
Contributions from non-controlling interests		0.5				0.5
Distributions		(72.8)		(46.6)		(26.2)
Unrealized gain on designated cash flow hedge	[4]	3.8	[2]		3.8
Common units repurchased		$ (12.5)		$ (12.5)
Common units repurchased (in shares)		(2,076,545)		(2,100,000)
Net income (loss)		$ 32.3		$ 1.9		30.4
Member equity, end balance at Sep. 30, 2021		3,055.2		$ 1,338.8	(4.2)	1,720.6
Units outstanding, end balance (in shares) at Sep. 30, 2021				488,000,000.0
Temporary Equity [Abstract]
Distributions		(72.8)		$ (46.6)		(26.2)
Redeemable noncontrolling interest, ending balance at Sep. 30, 2021							$ 0.0
Member equity, beginning balance at Dec. 31, 2021		$ 2,987.0		$ 1,325.8	(1.4)	1,662.6
Units outstanding, beginning balance (in shares) at Dec. 31, 2021		484,277,258		484,300,000
Increase (Decrease) in Members' Equity
Conversion of unit-based awards for common units, net of units withheld for taxes		$ (4.2)		$ (4.2)
Conversion of unit-based awards for common units, net of units withheld for taxes (in shares)				1,200,000
Unit-based compensation		8.1		$ 8.1
Contributions from non-controlling interests		7.3				7.3
Distributions		(91.0)		(56.4)		(34.6)
Unrealized gain on designated cash flow hedge		0.1			0.1
Redemption of non-controlling interest		(50.5)				(50.5)
Common units repurchased		(17.0)		$ (17.0)
Common units repurchased (in shares)				(2,100,000)
Net income (loss)		66.0		$ 35.2		30.8
Member equity, end balance at Mar. 31, 2022		2,905.8		$ 1,291.5	(1.3)	1,615.6
Units outstanding, end balance (in shares) at Mar. 31, 2022				483,400,000
Temporary Equity [Abstract]
Distributions		(91.0)		$ (56.4)		(34.6)
Member equity, beginning balance at Dec. 31, 2021		$ 2,987.0		$ 1,325.8	(1.4)	1,662.6
Units outstanding, beginning balance (in shares) at Dec. 31, 2021		484,277,258		484,300,000
Increase (Decrease) in Members' Equity
Unrealized gain on designated cash flow hedge	[2]	$ 0.1
Common units repurchased		$ (113.2)
Common units repurchased (in shares)		(12,272,440)
Member equity, end balance at Sep. 30, 2022		$ 2,874.0		$ 1,259.2	(1.3)	1,616.1
Units outstanding, end balance (in shares) at Sep. 30, 2022		474,566,135		474,600,000
Member equity, beginning balance at Mar. 31, 2022		$ 2,905.8		$ 1,291.5	(1.3)	1,615.6
Units outstanding, beginning balance (in shares) at Mar. 31, 2022				483,400,000
Increase (Decrease) in Members' Equity
Conversion of unit-based awards for common units, net of units withheld for taxes		(0.2)		$ (0.2)
Unit-based compensation		5.7		5.7
Contributions from non-controlling interests		2.0				2.0
Distributions		(97.5)		(55.3)		(42.2)
Common units repurchased		(33.7)		$ (33.7)
Common units repurchased (in shares)				(3,600,000)
Net income (loss)		123.9		$ 85.3		38.6
Member equity, end balance at Jun. 30, 2022		2,906.0		$ 1,293.3	(1.3)	1,614.0
Units outstanding, end balance (in shares) at Jun. 30, 2022				479,800,000
Temporary Equity [Abstract]
Distributions		(97.5)		$ (55.3)		(42.2)
Conversion of unit-based awards for common units, net of units withheld for taxes		(8.1)		$ (8.1)
Conversion of unit-based awards for common units, net of units withheld for taxes (in shares)				1,400,000
Unit-based compensation		11.4		$ 11.4
Contributions from non-controlling interests		4.9				4.9
Distributions		(94.3)		(55.7)		(38.6)
Unrealized gain on designated cash flow hedge	[2]	0.0
Common units repurchased		$ (62.5)		$ (62.5)
Common units repurchased (in shares)		(6,582,133)		(6,600,000)
Net income (loss)		$ 116.6		$ 80.8		35.8
Member equity, end balance at Sep. 30, 2022		$ 2,874.0		$ 1,259.2	$ (1.3)	1,616.1
Units outstanding, end balance (in shares) at Sep. 30, 2022		474,566,135		474,600,000
Temporary Equity [Abstract]
Distributions		$ (94.3)		$ (55.7)		$ (38.6)

[1] Includes tax expense of $1.1 million.

[2] Includes tax expense of $1.2 million and $3.4 million for the three and nine months ended September 30, 2021, respectively.

[3] Includes tax expense of $1.1 million.

[4] Includes tax expense of $1.2 million.