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Disaggregation of oil, gas, and NGL production revenue (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Segment Reporting [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	$ 2,156	$ 785	$ 3,633	$ 1,625
Revenue, Remaining Performance Obligation, Amount	0		0
Midland Basin
Segment Reporting [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	1,110	342	1,839	735
DJ Basin
Segment Reporting [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	579	0	921	0
South Texas
Segment Reporting [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	181	211	381	444
Uinta Basin
Segment Reporting [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	$ 286	$ 232	$ 492	$ 446
Revenue Benchmark \| Geographic Concentration Risk \| Midland Basin
Segment Reporting [Line Items]
Relative percentage	51.00%	43.00%	51.00%	45.00%
Revenue Benchmark \| Geographic Concentration Risk \| DJ Basin
Segment Reporting [Line Items]
Relative percentage	27.00%	0.00%	25.00%	0.00%
Revenue Benchmark \| Geographic Concentration Risk \| South Texas
Segment Reporting [Line Items]
Relative percentage	8.00%	27.00%	10.00%	27.00%
Revenue Benchmark \| Geographic Concentration Risk \| Uinta Basin
Segment Reporting [Line Items]
Relative percentage	13.00%	30.00%	14.00%	28.00%
Crude Oil
Segment Reporting [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	$ 2,026	$ 653	$ 3,288	$ 1,312
Crude Oil \| Midland Basin
Segment Reporting [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	1,135	315	1,835	651
Crude Oil \| DJ Basin
Segment Reporting [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	486	0	753	0
Crude Oil \| South Texas
Segment Reporting [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	125	113	221	231
Crude Oil \| Uinta Basin
Segment Reporting [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	280	225	479	430
Natural Gas
Segment Reporting [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	15	78	139	198
Natural Gas \| Midland Basin
Segment Reporting [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	(53)	27	(40)	83
Natural Gas \| DJ Basin
Segment Reporting [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	43	0	87	0
Natural Gas \| South Texas
Segment Reporting [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	19	44	79	99
Natural Gas \| Uinta Basin
Segment Reporting [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	6	6	13	16
Natural Gas Liquids (NGL)
Segment Reporting [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	115	54	206	115
Natural Gas Liquids (NGL) \| Midland Basin
Segment Reporting [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	28	0	44	0
Natural Gas Liquids (NGL) \| DJ Basin
Segment Reporting [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	50	0	81	0
Natural Gas Liquids (NGL) \| South Texas
Segment Reporting [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	37	54	81	114
Natural Gas Liquids (NGL) \| Uinta Basin
Segment Reporting [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	$ 0	$ 0	$ 0	$ 0