CONSOLIDATED STATEMENTS OFCASH FLOWS - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income (loss) including noncontrolling interests		$ 80,484	$ (1,338,900)	$ (239)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Unrealized derivative instrument loss		36,080	8,470	0
Depreciation and accretion		15,945	41,480	20,068
Deferred income tax expense (benefit)		0	64,915	(9,460)
Income from equity method interests, net		(58,739)	(19,069)	0
Distributions from equity method interests		80,747	25,316	0
Impairments		1,643	1,300,719	0
Adjustment for non-cash transactions with affiliate	[1]	0	0	(4,238)
Other	[1]	3,368	907	0
Changes in operating assets and liabilities:
(Increase) decrease in inventories		430	(620)	(5,058)
(Increase) decrease in prepaid assets and other		(56)	3,877	(1,045)
Increase in accounts receivable		(1,033)	0	0
(Increase) decrease in revenue receivables (Note 2)		4,083	(4,532)	(5,602)
(Increase) decrease in account receivables from/payable to affiliate		1,043	(6,361)	4,484
Increase in interest receivable		0	0	(226)
Increase in accrued expenses		280	71	1,977
Increase in deferred charges, deferred credits and other noncurrent liabilities		19	0	0
NET CASH PROVIDED BY OPERATING ACTIVITIES		164,294	76,273	661
CASH FLOWS FROM INVESTING ACTIVITIES:
Capital expenditures		(29,981)	(342,650)	(84,000)
Proceeds from sale of assets		10,240	13,309	0
Contributions to equity method interests		(327,305)	(501,352)	0
Distributions from equity method interests		17,419	0	0
Acquisition of equity method interests		0	(670,625)	(91,100)
Capitalized interest paid		(8,733)	(2,370)	0
NET CASH USED IN INVESTING ACTIVITIES		(338,360)	(1,503,688)	(175,100)
CASH FLOWS FROM FINANCING ACTIVITIES:
Redeemable noncontrolling interest - Preferred Unit limited partners, net		0	611,249	0
Distributions paid to Preferred Unit limited partners		(23,124)	0	0
Proceeds from revolving credit facility		228,000	396,000	0
Finance lease		(11,789)	(22,994)	0
Recapitalization transaction (Note 2)		0	0	628,154
Deferred facility fees		(816)	(792)	(3,780)
NET CASH PROVIDED BY FINANCING ACTIVITIES		192,271	983,463	624,374
INCREASE (DECREASE) IN CASH AND CASH EQUIVALENTS		18,205	(443,952)	449,935
CASH AND CASH EQUIVALENTS AT BEGINNING OF YEAR		5,983	449,935	0
CASH AND CASH EQUIVALENTS AT END OF PERIOD		24,188	5,983	449,935
SUPPLEMENTAL CASH FLOW DATA:
Accrued capital expenditures	[2]	834	18,573	89,810
Finance lease liability	[3]	0	9,767	0
Interest paid, net of capitalized interest		1,013	903	0
Cash received for income tax refunds		$ 696	$ 527	$ 0

[1] Prior to the Business Combination, the Company had no banking or cash management activities. Transactions with Apache and asset transfers to and from the Company were not settled in cash and are therefore reflected as a component of equity and redeemable noncontrolling interests on the consolidated balance sheet. In addition to the above, Apache contributed its investments in gas gathering, processing, and transmission facilities of approximately $484.5 million, that is included within equity and redeemable noncontrolling interests for the year ended December 31, 2018. Refer to Note 3—Transactions with Affiliates for more information.

[2] Includes $0.4 million, $1.5 million, and $9.1 million of capital expenditures due to Apache for the years ended December 31, 2020, 2019, and 2018, respectively, pursuant to the terms of the Construction, Operations, and Maintenance Agreement entered into at the closing of the Business Combination. Refer to Note 3—Transactions with Affiliates for more information.

[3] The Company entered into a finance lease in the first quarter of 2019 for power generators, which ended during the first quarter of 2020. The Company then exercised its option to purchase the generators.