Pension and Other Postretirement Benefit Plans - Components of Other Comprehensive Income (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Other Postretirement Benefits
Defined Benefit Plan Disclosure [Line Items]
Net loss (gain) amortization included in benefit cost	$ 0	$ 156	$ 199
Prior service (cost) credit arising during the period	0	0	0
Total	0	156	199
Net loss (gain) amortization included in benefit cost	(43)	(42)	(18)
Prior service credit amortization included in benefit cost	(57)	(63)	(73)
Settlements and curtailments	(1)	(29)	(4)
Total	(101)	(134)	(95)
United States | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Net loss (gain) amortization included in benefit cost	(42)	813	(472)
Prior service (cost) credit arising during the period	0	0	0
Total	(42)	813	(472)
Net loss (gain) amortization included in benefit cost	128	298	303
Prior service credit amortization included in benefit cost	(32)	(38)	(49)
Settlements and curtailments	251	232	23
Total	347	492	277
International | Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Net loss (gain) amortization included in benefit cost	116	772	(424)
Prior service (cost) credit arising during the period	(4)	(4)	64
Total	112	768	(360)
Net loss (gain) amortization included in benefit cost	96	142	127
Prior service credit amortization included in benefit cost	(14)	(16)	(18)
Settlements and curtailments	1	(18)	15
Total	$ 83	$ 108	$ 124