Capital Accounts, Summary of Changes in Outstanding Units (Details)	3 Months Ended
	Mar. 31, 2021 shares
Summary of changes in outstanding units [Roll Forward]
Number of common units outstanding, beginning balance (in units)	2,182,308,958
Common unit repurchases under 2019 Buyback Program (in units)	(709,816)
Common units issued in connection with the vesting of phantom unit awards, net (in units)	3,553,313
Other (in units)	26,148
Number of common units outstanding, ending balance (in units)	2,185,178,603