Other Comprehensive Income (Loss) - Schedule of Other Comprehensive Income Amounts Reclassified to Statement of Operations (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Sales and other revenues:	$ 7,251	$ 7,207	$ 20,405	$ 22,080
Other, net	(2)	4	(48)	5
Income tax expense (benefit)	123	(57)	160	52
Net of tax	405	(74)	613	396
Reclassification out of Accumulated Other Comprehensive Income (Loss)
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net of tax	1	0	2	(3)
Reclassification out of Accumulated Other Comprehensive Income (Loss) | Hedging instruments:
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Sales and other revenues:	0	(1)	0	(5)
Income tax expense (benefit)	0	(1)	0	(1)
Net of tax	0	0	0	(4)
Reclassification out of Accumulated Other Comprehensive Income (Loss) | Other post-retirement benefit obligations: | Pension obligations
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other, net	0	(1)	0	(1)
Income tax expense (benefit)	0	0	0	0
Net of tax	0	(1)	0	(1)
Reclassification out of Accumulated Other Comprehensive Income (Loss) | Other post-retirement benefit obligations: | Post-retirement healthcare obligations
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Other, net	1	1	3	3
Income tax expense (benefit)	0	0	1	1
Net of tax	$ 1	$ 1	$ 2	$ 2