SERIES A CUMULATIVE REDEEMABLE PREFERRED UNITS - Activity Related to Preferred Units (Details) - USD ($) shares in Thousands, $ in Thousands		3 Months Ended		12 Months Ended
		Mar. 31, 2021		Dec. 31, 2020
Increase (Decrease) in Temporary Equity [Roll Forward]
Beginning balance	[1]	$ 608,381
Allocation of Altus Midstream net income		19,492
Ending balance		604,749		$ 608,381	[1]
Embedded derivative liability		155,538		$ 139,009	[1]
Redeemable noncontrolling interest, including embedded derivative liability		$ 760,287
Preferred Units, redemption terms, internal rate of return		11.50%
Preferred Units, redemption terms, multiple of invested capital		1.3
Preferred Units, invested capital		$ 812,500
Preferred Units, redemption price		$ 713,000
Preferred Unit limited partners
Movement In Preferred Units [Roll Forward]
Redeemable noncontrolling interest - Preferred Units: beginning of period (in shares)		660,694		638,163
Distribution of in-kind additional Preferred Units (in shares)				22,531
Redeemable noncontrolling interest - Preferred Units: end of period (in shares)		660,694		660,694
Increase (Decrease) in Temporary Equity [Roll Forward]
Beginning balance		$ 608,381		$ 555,599
Cash distributions paid to Preferred Unit limited partners		(11,562)	[2]	(23,124)
Allocation of Altus Midstream net income				75,906
Distributions payable to Preferred Unit limited partners	[2]	(11,562)
Ending balance		$ 604,749		$ 608,381

[1] The Consolidated Balance Sheet as of December 31, 2020 has been derived from the audited consolidated financial statements, revised to reflect the Company’s fair value change of its underlying warrants. Refer to Note 1—Summary of Significant Accounting Policies, see the section titled Revision of Previously Issued Consolidated Financial Statements for Immaterial Adjustment for further information.

[2] Certain redemption features embedded within the Preferred Units require bifurcation and measurement at fair value. For further detail, refer to Note 10—Series A Cumulative Redeemable Preferred Units.