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Goodwill and Other Intangible Assets - Changes In The Carrying Amount Of Goodwill (Details) € in Millions, $ in Millions	3 Months Ended	6 Months Ended		12 Months Ended
	Jun. 30, 2021 USD ($)	Jun. 30, 2021 USD ($)	Jun. 30, 2021 EUR (€)	Dec. 31, 2020 USD ($)
Goodwill [Roll Forward]
Beginning balance		$ 7,683		$ 7,556
Foreign currency translation		(42)		127
Acquisitions		5
Divestitures		(17)
Ending balance	$ 7,629	7,629		7,683
Disposal Group, Disposed of by Sale, Not Discontinued Operations \| WMS
Goodwill [Roll Forward]
Gain on sale of business	53
Investment Servicing
Goodwill [Roll Forward]
Beginning balance		7,413		7,289
Foreign currency translation		(42)		124
Acquisitions		5
Divestitures		(17)
Ending balance	7,359	7,359		7,413
Investment Servicing \| Fideuram Bank Luxembour
Goodwill [Roll Forward]
Payments for acquisition		258	€ 220
Investment Management
Goodwill [Roll Forward]
Beginning balance		270		267
Foreign currency translation		0		3
Acquisitions		0
Divestitures		0
Ending balance	$ 270	$ 270		$ 270