Goodwill and Other Intangible Assets - Changes In The Carrying Amount Of Other Intangible Assets (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Finite-lived Intangible Assets [Roll Forward]
Beginning balance	$ 2,030	$ 2,369
Acquisitions		(93)
Amortization	(234)	(236)	$ (226)
Foreign currency translation	31	(10)
Ending balance	1,827	2,030	2,369
Investment Servicing
Finite-lived Intangible Assets [Roll Forward]
Beginning balance	1,908	2,218
Acquisitions		(93)
Amortization	(206)	(207)
Foreign currency translation	31	(10)
Ending balance	1,733	1,908	2,218
Investment Management
Finite-lived Intangible Assets [Roll Forward]
Beginning balance	122	151
Acquisitions		0
Amortization	(28)	(29)
Foreign currency translation	0	0
Ending balance	94	$ 122	$ 151
CRD Acquisition
Finite-lived Intangible Assets [Roll Forward]
Acquisitions	$ (93)

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.

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

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

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Amount of increase (decrease) to assets, excluding financial assets and goodwill, lacking physical substance with a finite life for purchase accounting adjustments.

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