Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Cash flows from operating activities:
Net income (loss)	$ 105,846	$ 134,115
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for deferred income taxes	7,754	22,850
Depreciation, amortization and accretion	35,596	31,798
Amortization of debt issuance costs	467	0
(Gain) loss on disposal of property, plant and equipment	2,765	(4)
Unit-based compensation expense	6,555	2,989
(Income) loss from equity method investments	9,910	695
Changes in operating assets and liabilities:
Accounts receivable—related party	1,649	(45,297)
Accounts receivable—third party	(314)	(1,045)
Accounts payable, accrued liabilities and taxes payable	117	30,791
Other	7,029	(13,028)
Net cash provided by (used in) operating activities	177,374	163,864
Cash flows from investing activities:
Additions to property, plant and equipment	(124,989)	(187,544)
Contributions to equity method investments	(89,751)	(76,141)
Distributions from equity method investments	27,490	0
Proceeds from the sale of fixed assets	42	18
Net cash provided by (used in) investing activities	(187,208)	(263,667)
Cash flows from financing activities:
Proceeds from senior notes	500,000	0
Proceeds from borrowings from credit facility	179,000	112,000
Payments on credit facility	(518,000)	(9,000)
Distribution equivalent rights	(1,820)	0
Debt issuance costs	(10,014)	(3,929)
Net proceeds from initial public offering—public	0	719,376
Net proceeds from initial public offering—General Partner	0	1,000
Net proceeds from initial public offering—Diamondback	0	999
Units repurchased for tax withholding	(1,365)	0
Distribution to General Partner (Note 1)	(60)	0
Distribution to public (Note 1)	(38,104)	0
Distribution to Diamondback (Note 1)	(93,860)	(726,513)
Net cash provided by (used in) financing activities	15,777	93,933
Net increase (decrease) in cash	5,943	(5,870)
Cash at beginning of period	10,633	8,564
Cash at end of period	16,576	2,694
Supplemental disclosure of non-cash financing activity:
Contributions from Diamondback	0	456,055
Supplemental disclosure of non-cash investing activity:
Increase in long term assets and inventory due to contributions from Diamondback	0	456,055
Accounts payable related to capital expenditures	$ 13,689	$ 57,002