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Disaggregation of oil, gas, and NGL production revenue (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025
Segment Reporting [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	$ 2,160	$ 811	$ 5,793	$ 2,436
Revenue, Remaining Performance Obligation, Amount	0		0
Midland Basin
Segment Reporting [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	1,103	344	2,942	1,079
DJ Basin
Segment Reporting [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	580	0	1,501	0
South Texas
Segment Reporting [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	184	235	565	680
Uinta Basin
Segment Reporting [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	$ 293	$ 232	$ 785	$ 677
Revenue Benchmark \| Geographic Concentration Risk \| Midland Basin
Segment Reporting [Line Items]
Relative percentage	51.00%	42.00%	51.00%	44.00%
Revenue Benchmark \| Geographic Concentration Risk \| DJ Basin
Segment Reporting [Line Items]
Relative percentage	27.00%	0.00%	26.00%	0.00%
Revenue Benchmark \| Geographic Concentration Risk \| South Texas
Segment Reporting [Line Items]
Relative percentage	9.00%	29.00%	10.00%	28.00%
Revenue Benchmark \| Geographic Concentration Risk \| Uinta Basin
Segment Reporting [Line Items]
Relative percentage	13.00%	29.00%	13.00%	28.00%
Crude Oil
Segment Reporting [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	$ 1,816	$ 669	$ 5,104	$ 1,981
Crude Oil \| Midland Basin
Segment Reporting [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	944	312	2,779	963
Crude Oil \| DJ Basin
Segment Reporting [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	460	0	1,213	0
Crude Oil \| South Texas
Segment Reporting [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	127	131	348	362
Crude Oil \| Uinta Basin
Segment Reporting [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	285	226	764	656
Natural Gas
Segment Reporting [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	209	84	348	282
Natural Gas \| Midland Basin
Segment Reporting [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	123	32	83	115
Natural Gas \| DJ Basin
Segment Reporting [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	60	0	147	0
Natural Gas \| South Texas
Segment Reporting [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	18	47	97	146
Natural Gas \| Uinta Basin
Segment Reporting [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	8	6	21	21
Natural Gas Liquids (NGL)
Segment Reporting [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	135	58	341	172
Natural Gas Liquids (NGL) \| Midland Basin
Segment Reporting [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	36	0	80	0
Natural Gas Liquids (NGL) \| DJ Basin
Segment Reporting [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	60	0	141	0
Natural Gas Liquids (NGL) \| South Texas
Segment Reporting [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	39	58	120	172
Natural Gas Liquids (NGL) \| Uinta Basin
Segment Reporting [Line Items]
Revenue from Contract with Customer, Including Assessed Tax	$ 0	$ 0	$ 0	$ 0