Goodwill and Other Intangible Assets - Changes In The Carrying Amount Of Other Intangible Assets (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Finite-lived Intangible Assets [Roll Forward]
Beginning balance	$ 1,613	$ 1,750
Acquisitions	1,007	16
Divestitures		(11)
Amortization	(226)	(214)	$ (207)
Foreign currency translation	(25)	72
Ending balance	2,369	1,613	1,750
Investment Servicing
Finite-lived Intangible Assets [Roll Forward]
Beginning balance	1,432	1,539
Acquisitions	1,007	16
Divestitures		(11)
Amortization	(196)	(183)
Foreign currency translation	(25)	71
Ending balance	2,218	1,432	1,539
Investment Management
Finite-lived Intangible Assets [Roll Forward]
Beginning balance	181	211
Acquisitions	0	0
Divestitures		0
Amortization	(30)	(31)
Foreign currency translation	0	1
Ending balance	$ 151	$ 181	$ 211

Finite-Lived Intangible Assets, Divestiture

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- Definition

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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-Section 45
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- Definition

Amount of foreign currency translation gain (loss) which increases (decreases) assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

No definition available.

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- Definition

Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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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.

+ References

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- Definition

Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
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-Paragraph 1
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