Income Taxes, Reconciliation of Income Tax Expense (Benefit) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Foreign tax effects:
Worldwide changes in unrecognized tax benefits	$ 27	$ 145	$ (51)
Income tax expense	$ 759	$ 692	$ 2,619
Foreign tax effects:
Worldwide changes in unrecognized tax benefits (percent)	0.90%	3.90%	(0.40%)
Income tax expense (percent)	25.30%	18.70%	22.30%
U.S. [Member]
Effective Income Tax Rate Reconciliation, Amount
U.S. federal statutory income tax rate	$ 631	$ 777	$ 2,471
Tax credits
Foreign tax credits	(61)	(46)	(149)
Biofuels tax credits	(4)	(248)	0
Other	(1)	(1)	(1)
Nontaxable and nondeductible items
Nontaxable production tax credits	(66)	0	0
Nontaxable blender's tax credits	0	(127)	(125)
Tax on biofuels tax credits	1	52	0
Other	13	14	34
Cross-border tax laws	4	7	27
Changes in valuation allowances	63	49	149
Other reconciling items
Tax effects of income associated with noncontrolling interests	25	(50)	(84)
Other	(3)	(43)	34
Domestic state and local income taxes, net of federal effect	22	19	122
Foreign tax effects:
Provincial and local income taxes	22	19	122
Changes in valuation allowances	$ 63	$ 49	$ 149
Effective Income Tax Rate Reconciliation, Percent
U.S. federal statutory income tax rate (percent)	21.00%	21.00%	21.00%
Tax credits
Foreign tax credits (percent)	(2.00%)	(1.20%)	(1.30%)
Biofuels tax credits (percent)	(0.10%)	(6.70%)	0.00%
Other (percent)	0.00%	0.00%	0.00%
Nontaxable and nondeductible items
Nontaxable production tax credits (percent)	(2.20%)	0.00%	0.00%
Nontaxable blender's tax credits (percent)	0.00%	(3.40%)	(1.10%)
Tax on biofuels tax credits (percent)	0.00%	1.40%	0.00%
Other (percent)	0.40%	0.40%	0.30%
Cross-border tax laws (percent)	0.10%	0.20%	0.20%
Changes in valuation allowances (percent)	2.10%	1.30%	1.30%
Other reconciling items
Tax effects of income associated with noncontrolling interests (percent)	0.80%	(1.30%)	(0.70%)
Other (percent)	(0.10%)	(1.20%)	0.30%
Domestic state and local income taxes, net of federal effect (percent)	0.70%	0.50%	1.00%
Foreign tax effects:
Provincial and local income taxes (percent)	0.70%	0.50%	1.00%
Changes in valuation allowances (percent)	2.10%	1.30%	1.30%
Canada [Member]
Other reconciling items
Domestic state and local income taxes, net of federal effect	$ 90	$ 101	$ 161
Foreign tax effects:
Provincial and local income taxes	90	101	161
Statutory income tax rate differential	(47)	(52)	(84)
Withholding taxes	41	59	45
Other	0	(2)	21
Other foreign	$ (47)	$ (52)	$ (84)
Other reconciling items
Domestic state and local income taxes, net of federal effect (percent)	3.00%	2.70%	1.40%
Foreign tax effects:
Provincial and local income taxes (percent)	3.00%	2.70%	1.40%
Statutory income tax rate differential (percent)	(1.50%)	(1.40%)	(0.70%)
Withholding taxes (percent)	1.40%	1.60%	0.40%
Other (percent)	0.00%	(0.10%)	0.20%
Other foreign (percent)	(1.50%)	(1.40%)	(0.70%)
Mexico [Member]
Nontaxable and nondeductible items
Changes in valuation allowances	$ (61)	$ 57	$ 0
Foreign tax effects:
Changes in valuation allowances	(61)	57	0
Statutory income tax rate differential	42	(26)	15
Other	1	(4)	35
Other foreign	$ 42	$ (26)	$ 15
Nontaxable and nondeductible items
Changes in valuation allowances (percent)	(2.00%)	1.50%	0.00%
Foreign tax effects:
Changes in valuation allowances (percent)	(2.00%)	1.50%	0.00%
Statutory income tax rate differential (percent)	1.40%	(0.70%)	0.10%
Other (percent)	0.00%	(0.10%)	0.30%
Other foreign (percent)	1.40%	(0.70%)	0.10%
United Kingdom [Member]
Foreign tax effects:
Statutory income tax rate differential	$ 33	$ 14	$ 19
Other	1	1	(13)
Other foreign	$ 33	$ 14	$ 19
Foreign tax effects:
Statutory income tax rate differential (percent)	1.10%	0.40%	0.20%
Other (percent)	0.00%	0.00%	(0.10%)
Other foreign (percent)	1.10%	0.40%	0.20%
Other Foreign [Member]
Foreign tax effects:
Statutory income tax rate differential	$ 8	$ (4)	$ (7)
Other foreign	$ 8	$ (4)	$ (7)
Foreign tax effects:
Statutory income tax rate differential (percent)	0.30%	(0.10%)	(0.10%)
Other foreign (percent)	0.30%	(0.10%)	(0.10%)