Post-Employment Benefits - Pretax Gains and Losses Included in Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Defined benefit plans
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Actuarial loss (gain)	$ (16)	$ (925)	$ (345)
Amortization of prior service credit (cost)	(1)	(2)	(2)
Amortization of actuarial loss	(16)	(231)	(288)
Foreign exchange loss (gain) and other	(44)	17	(27)
Total loss (gain)	(77)	(1,141)	(662)
Other post-employment plans
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Actuarial loss (gain)	89	(229)	10
Amortization of prior service credit (cost)	36	38	39
Amortization of actuarial loss	(12)	(26)	(32)
Prior service credit	0	(2)	0
Total loss (gain)	$ 113	$ (219)	$ 17