Other Assets - Goodwill (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 3,786	$ 3,804
Acquisitions	48	13
Dispositions	0	0
Other	17	(31)
Goodwill, ending balance	3,851	3,786
USCS
Goodwill [Roll Forward]
Goodwill, beginning balance	379	368
Acquisitions	0	13
Dispositions	0	0
Other	0	(2)
Goodwill, ending balance	379	379
CS
Goodwill [Roll Forward]
Goodwill, beginning balance	2,122	2,123
Acquisitions	30	0
Dispositions	0	0
Other	(1)	(1)
Goodwill, ending balance	2,151	2,122
ICS
Goodwill [Roll Forward]
Goodwill, beginning balance	725	753
Acquisitions	0	0
Dispositions	0	0
Other	18	(28)
Goodwill, ending balance	743	725
GMNS
Goodwill [Roll Forward]
Goodwill, beginning balance	560	560
Acquisitions	18	0
Dispositions	0	0
Other	0	0
Goodwill, ending balance	$ 578	$ 560