Benefit Plans - Changes not yet recognized (Details) $ in Millions	12 Months Ended
	Dec. 31, 2021 USD ($)
Pension benefits
Change in items not yet recognized as a component of defined benefit plans, net periodic cost
Items not yet recognized as a component of net cost – December 31, 2020	$ (78)
Prior service credit amortized to net cost	50
Translation adjustment and other	0
Items not yet recognized as a component of net cost – December 31, 2021	(28)
Postretirement benefits
Change in items not yet recognized as a component of defined benefit plans, net periodic cost
Items not yet recognized as a component of net cost – December 31, 2020	(89)
Prior service credit amortized to net cost	25
Translation adjustment and other	(1)
Items not yet recognized as a component of net cost – December 31, 2021	$ (65)