Benefit Plans - Changes in benefit obligations (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Change in benefit obligation
Service cost	$ 102	$ 104	$ 108
Interest cost	229	199	221
Pension benefits
Change in benefit obligation
Benefit obligation, beginning of year	6,500	7,763
Service cost	101	103	104
Interest cost	219	191	210
Participant contributions	0	0
Remeasurement of projected benefit obligation (gains) losses	(1,382)	(309)
Benefits paid	(894)	(1,242)
Translation adjustment and other	(33)	(6)
Benefit obligation, end of year	4,511	6,500	7,763
Change in plan assets
Fair value of plan assets, beginning of year	6,525	6,987
Actual return on plan assets	(1,189)	764
Employer contribution	24	22
Benefits paid	(894)	(1,242)
Translation adjustment and other	(36)	(6)
Fair value of plan assets, end of year	4,430	6,525	6,987
Funded status	(81)	25
Prior service credit	0
Unamortized pension and other postretirement prior service credit	0	(28)
Postretirement benefits
Change in benefit obligation
Benefit obligation, beginning of year	284	318
Service cost	1	1	4
Interest cost	10	8	11
Participant contributions	16	16
Remeasurement of projected benefit obligation (gains) losses	(62)	(16)
Benefits paid	(42)	(43)
Translation adjustment and other	(4)	0
Benefit obligation, end of year	203	284	$ 318
Change in plan assets
Fair value of plan assets, beginning of year
Employer contribution	26	27
Fair value of plan assets, end of year
Funded status	(203)	(284)
Prior service credit	(39)
Unamortized pension and other postretirement prior service credit	$ (39)	$ (65)