Postretirement Benefit Plans - Benefit Obligations and Plan Assets (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Change in plan assets
Funded status at end of year	$ 303	$ 104
U.S. | Defined Benefit
Change in plan benefit obligation
Benefit obligation at beginning of year:	1,097	960
Service cost	21	18	$ 18
Interest cost	30	31	38
Participant contributions	0	0
Benefits paid	(12)	(12)
Settlements	(162)	(94)
Actuarial loss (gain)	(79)	194
Plan amendments	0	0
Effects of exchange rate changes	0	0
Benefit obligation at end of year	895	1,097	960
Change in plan assets
Fair value of plan assets at beginning of year:	1,061	987
Actual return on plan assets	37	164
Employer contributions (qualified plans)	0	0
Employer contributions (non-qualified plans)	10	16
Participant contributions	0	0
Benefits paid	(12)	(12)
Settlements	(162)	(94)
Effects of exchange rate changes	0	0
Fair value of plan assets at end of year	934	1,061	987
Funded status at end of year	39	(36)
U.S. | Retiree Health Care
Change in plan benefit obligation
Benefit obligation at beginning of year:	389	359
Service cost	3	3	3
Interest cost	10	13	14
Participant contributions	14	13
Benefits paid	(38)	(39)
Settlements	0	0
Actuarial loss (gain)	(18)	40
Plan amendments	0	0
Effects of exchange rate changes	0	0
Benefit obligation at end of year	360	389	359
Change in plan assets
Fair value of plan assets at beginning of year:	389	356
Actual return on plan assets	19	58
Employer contributions (qualified plans)	1	1
Employer contributions (non-qualified plans)	0	0
Participant contributions	14	13
Benefits paid	(38)	(39)
Settlements	0	0
Effects of exchange rate changes	0	0
Fair value of plan assets at end of year	385	389	356
Funded status at end of year	25	0
Non-U.S. | Defined Benefit
Change in plan benefit obligation
Benefit obligation at beginning of year:	2,868	2,581
Service cost	36	34	31
Interest cost	37	38	43
Participant contributions	9	7
Benefits paid	(101)	(95)
Settlements	(12)	(8)
Actuarial loss (gain)	(111)	143
Plan amendments	0	1
Effects of exchange rate changes	(152)	167
Benefit obligation at end of year	2,574	2,868	2,581
Change in plan assets
Fair value of plan assets at beginning of year:	3,008	2,661
Actual return on plan assets	75	260
Employer contributions (qualified plans)	7	11
Employer contributions (non-qualified plans)	0	0
Participant contributions	9	7
Benefits paid	(101)	(95)
Settlements	(12)	(8)
Effects of exchange rate changes	(173)	172
Fair value of plan assets at end of year	2,813	3,008	$ 2,661
Funded status at end of year	$ 239	$ 140