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Goodwill and Other Intangible Assets - Changes in the Carrying Amount of Goodwill (Details) € in Millions, $ in Millions	3 Months Ended			9 Months Ended	12 Months Ended
	Sep. 30, 2021 USD ($)	Mar. 31, 2021 USD ($)	Mar. 31, 2021 EUR (€)	Sep. 30, 2022 USD ($)	Dec. 31, 2021 USD ($)
Goodwill [Roll Forward]
Beginning balance		$ 7,683		$ 7,621	$ 7,683
Acquisitions				3	66
Divestitures					(17)
Foreign currency translation				(273)	(111)
Ending balance				7,351	7,621
Investment Servicing
Goodwill [Roll Forward]
Beginning balance		7,413		7,354	7,413
Acquisitions				3	66
Divestitures					(17)
Foreign currency translation				(265)	(108)
Ending balance				7,092	7,354
Investment Servicing \| Fideuram Bank Luxembour
Goodwill [Roll Forward]
Payment for acquisition		258	€ 220
Investment Servicing \| Mercatus, Inc
Goodwill [Roll Forward]
Payment for acquisition	$ 88
Investment Management
Goodwill [Roll Forward]
Beginning balance		$ 270		267	270
Acquisitions				0	0
Divestitures					0
Foreign currency translation				(8)	(3)
Ending balance				$ 259	$ 267