Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Increase (Decrease) in Accumulated Other Comprehensive Income
Beginning balance	$ 12,905	$ 13,545
Other comprehensive income (loss), net of tax	(117)	(55)
Other comprehensive loss, net of tax	(117)	(55)	$ (8)
Ending balance	13,009	12,905	13,545
Accumulated other comprehensive income
Increase (Decrease) in Accumulated Other Comprehensive Income
Beginning balance	(234)	(179)
Ending balance	(351)	(234)	(179)
Pension Plans
Increase (Decrease) in Accumulated Other Comprehensive Income
Beginning balance	(13)	2
Other comprehensive income (loss), net of tax	16	(15)
Other comprehensive loss, net of tax	16	(15)
Ending balance	3	(13)	2
Foreign Currency Translation Adjustments and Other
Increase (Decrease) in Accumulated Other Comprehensive Income
Beginning balance	(221)	(181)
Other comprehensive income (loss), net of tax	(133)	(40)
Other comprehensive loss, net of tax	(133)	(40)
Ending balance	$ (354)	$ (221)	$ (181)