Employee Benefit Plans, Pre-Tax Amounts Recognized in Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Net (gain) loss reclassified into income:
Total changes in other comprehensive income (loss)	$ 30	$ 335	$ 378
Pension Plans [Member]
Net gain (loss) arising during the year:
Net actuarial gain (loss)	87	158	308
Prior service cost	(19)	0	(4)
Net (gain) loss reclassified into income:
Net actuarial (gain) loss	(6)	53	81
Prior service credit	(18)	(18)	(18)
Settlement loss	2	61	8
Effect of exchange rates	4	0	2
Total changes in other comprehensive income (loss)	50	254	377
Other Postretirement Benefit Plans [Member]
Net gain (loss) arising during the year:
Net actuarial gain (loss)	(10)	86	9
Prior service cost	0	0	0
Net (gain) loss reclassified into income:
Net actuarial (gain) loss	(6)	(1)	(1)
Prior service credit	(4)	(4)	(7)
Settlement loss	0	0	0
Effect of exchange rates	0	0	0
Total changes in other comprehensive income (loss)	$ (20)	$ 81	$ 1