v3.20.4

UNIT-BASED COMPENSATION Table 4 - Unit Awards (Details) - Share-based Payment Arrangement [Member] - USD ($) $ in Thousands	1 Months Ended		2 Months Ended	12 Months Ended
	Feb. 28, 2019	Jul. 31, 2018	Mar. 31, 2020	Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unit-based compensation, description of performance units				Unit awards are equity-classified awards of fully vested common units. We accrued compensation expense in 2019 and 2018 that was paid in unit awards in the first quarter of the subsequent year. We base the number of unit awards granted on the fair value of the common units at the grant date.
Weighted-average grant date fair value, granted	$ 17,537	$ 1,358	$ 22,941
Unit-based awards, granted (units)	704,886	55,133	834,224
Common Limited Partner [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Issuance of units (units)	482,971	35,745	571,735

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