Pension and Other Postretirement Benefit Plans - Accumulated and Projected Benefit Obligation in Excess of Plan Assets (Details) - Pension Benefits - USD ($) $ in Millions	Dec. 31, 2022	Dec. 31, 2021
United States
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Pension plans with a projected benefit obligation in excess of plan assets, projected benefit obligation	$ 9,186	$ 13,013
Pension plans with a projected benefit obligation in excess of plan assets, fair value of plan assets	8,421	12,072
Pension plans with an accumulated benefit obligation in excess of plan assets, accumulated benefit obligation	9,081	12,916
Pension plans with an accumulated benefit obligation in excess of plan assets, fair value of plan assets	8,421	12,072
International
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Pension plans with a projected benefit obligation in excess of plan assets, projected benefit obligation	2,779	2,507
Pension plans with a projected benefit obligation in excess of plan assets, fair value of plan assets	2,445	1,731
Pension plans with an accumulated benefit obligation in excess of plan assets, accumulated benefit obligation	1,226	2,462
Pension plans with an accumulated benefit obligation in excess of plan assets, fair value of plan assets	$ 948	$ 1,723