Goodwill and Other Intangible Assets - Changes in the Carrying Amount of Other Intangible Assets (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Finite-lived Intangible Assets [Roll Forward]
Beginning balance			$ 1,544	$ 1,816	$ 1,816
Amortization	$ (60)	$ (58)	(180)	(179)	(238)
Foreign currency translation			(1)		(34)
Ending balance	1,363		1,363		1,544
Investment Servicing
Finite-lived Intangible Assets [Roll Forward]
Beginning balance			1,495	1,746	1,746
Amortization			(164)		(217)
Foreign currency translation			(1)		(34)
Ending balance	1,330		1,330		1,495
Investment Management
Finite-lived Intangible Assets [Roll Forward]
Beginning balance			49	$ 70	70
Amortization			(16)		(21)
Foreign currency translation			0		0
Ending balance	$ 33		$ 33		$ 49