Equity-Based Awards, Phantom Unit Awards (Details) - USD ($) $ / shares in Units, $ in Millions		3 Months Ended		9 Months Ended
		Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Summary of awards activity, equity instruments other than options, additional disclosures [Abstract]
Cash payments made in connection with DERs				$ 23.1	$ 20.0
Phantom Unit Awards [Member]
Summary of awards activity, equity instruments other than options [Roll Forward]
Beginning of period (in units)				15,669,442
Granted (in units)	[1]			7,720,645
Vested (in units)				(5,574,695)
Forfeited (in units)				(514,907)
End of period (in units)		17,300,485		17,300,485
Phantom units outstanding, weighted-average grant date fair value [Roll Forward]
Weighted-average grant date fair value per unit, at beginning of period (in dollars per unit)	[2]			$ 26.76
Granted weighted-average grant date fair value per unit (in dollars per unit)	[1],[2]			21.30
Vested weighted-average grant date fair value per unit (in dollars per unit)	[2]			27.01
Forfeited weighted-average grant date fair value per unit (in dollars per unit)	[2]			24.48
Weighted-average grant date fair value per unit, at end of period (in dollars per unit)	[2]	$ 24.31		$ 24.31
Summary of awards activity, equity instruments other than options, additional disclosures [Abstract]
Aggregate grant date fair value				$ 164.4
Estimated forfeiture rate				2.00%
Cash payments made in connection with DERs		$ 7.9	$ 7.1	$ 23.1	20.0
Total intrinsic value of phantom unit awards that vested during period		3.5	$ 2.0	122.6	$ 113.4
Unrecognized Compensation Expense [Abstract]
Unrecognized compensation cost		185.1		$ 185.1
Recognition period for total unrecognized compensation cost				2 years
Phantom Unit Awards [Member] | Minimum [Member]
Summary of awards activity, equity instruments other than options, additional disclosures [Abstract]
Grant date market price of common units (in dollars per unit)				$ 20.79
Phantom Unit Awards [Member] | Maximum [Member]
Summary of awards activity, equity instruments other than options, additional disclosures [Abstract]
Grant date market price of common units (in dollars per unit)				$ 22.05
Phantom Unit Awards [Member] | Enterprise [Member]
Unrecognized Compensation Expense [Abstract]
Unrecognized compensation cost		$ 153.0		$ 153.0

[1] The aggregate grant date fair value of phantom unit awards issued during 2021 was $164.4 million based on a grant date market price of the Partnership’s common units ranging from $20.79 to $22.05 per unit.  An estimated annual forfeiture rate of 2.0% was applied to these awards.

[2] Determined by dividing the aggregate grant date fair value of awards (before an allowance for forfeitures) by the number of awards issued.