Goodwill and Other Intangible Assets - Changes In The Carrying Amount Of Goodwill (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Mar. 31, 2020	Dec. 31, 2019
Goodwill [Roll Forward]
Beginning balance	$ 7,556	$ 7,446
Acquisitions		122
Foreign currency translation	(50)	(12)
Ending balance	7,506	7,556
Investment Servicing
Goodwill [Roll Forward]
Beginning balance	7,289	7,180
Acquisitions		122
Foreign currency translation	(47)	(13)
Ending balance	7,242	7,289
Investment Management
Goodwill [Roll Forward]
Beginning balance	267	266
Acquisitions		0
Foreign currency translation	(3)	1
Ending balance	$ 264	$ 267

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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- Definition

Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of increase (decrease) from foreign currency translation adjustments and purchase accounting adjustments of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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