UNAUDITED CONDENSED CONSOLIDATED STATEMENTS OF PARTNERS' CAPITAL (DEFICIT) - USD ($) $ in Millions	General Partner's	Limited Partners	Accumulated other comprehensive loss	Total
Beginning balance at Dec. 31, 2021	$ 3.8	$ (378.8)	$ (10.1)	$ (385.1)
Increase (Decrease) in Partners' Capital
Other comprehensive income			0.2	0.2
Net income (loss) attributable to partners	(1.9)	(93.2)		(95.1)
Settlement of tax withholdings on equity-based incentive compensation		(4.1)		(4.1)
Settlement of phantom units		6.7		6.7
Modification of phantom units		13.5		13.5
Amortization of phantom units		4.0		4.0
Adjustment to ASC 480 redemption value		(5.5)		(5.5)
Ending balance at Sep. 30, 2022	1.9	(457.4)	(9.9)	(465.4)
Beginning balance at Jun. 30, 2022	1.6	(469.2)	(10.0)	(477.6)
Increase (Decrease) in Partners' Capital
Other comprehensive income			0.1	0.1
Net income (loss) attributable to partners	0.3	15.4		15.7
Settlement of phantom units		0.1		0.1
Amortization of phantom units		1.8		1.8
Adjustment to ASC 480 redemption value		(5.5)		(5.5)
Ending balance at Sep. 30, 2022	1.9	(457.4)	(9.9)	(465.4)
Beginning balance at Dec. 31, 2022	0.5	(529.9)	(8.3)	(537.7)
Increase (Decrease) in Partners' Capital
Other comprehensive income			0.2	0.2
Net income (loss) attributable to partners	2.3	110.9		113.2
Settlement of tax withholdings on equity-based incentive compensation		(9.6)		(9.6)
Settlement of phantom units		4.2		4.2
Amortization of phantom units		0.6		0.6
Adjustment to ASC 480 redemption value		(18.5)		(18.5)
Ending balance at Sep. 30, 2023	2.8	(442.3)	(8.1)	(447.6)
Beginning balance at Jun. 30, 2023	0.7	(540.3)	(8.2)	(547.8)
Increase (Decrease) in Partners' Capital
Other comprehensive income			0.1	0.1
Net income (loss) attributable to partners	2.1	100.9		103.0
Amortization of phantom units		0.2		0.2
Adjustment to ASC 480 redemption value		(3.1)		(3.1)
Ending balance at Sep. 30, 2023	$ 2.8	$ (442.3)	$ (8.1)	$ (447.6)