Goodwill and Other Intangible Assets - Changes In The Carrying Amount Of Other Intangible Assets (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Finite-lived Intangible Assets [Roll Forward]
Beginning balance	$ 2,030	$ 2,369	$ 2,369
Acquisitions			(93)
Amortization	(58)	(60)	(236)
Foreign currency translation	(9)		(10)
Ending balance	1,963		2,030
Investment Servicing
Finite-lived Intangible Assets [Roll Forward]
Beginning balance	1,908	2,218	2,218
Acquisitions			(93)
Amortization	(51)		(207)
Foreign currency translation	(9)		(10)
Ending balance	1,848		1,908
Investment Management
Finite-lived Intangible Assets [Roll Forward]
Beginning balance	122	$ 151	151
Acquisitions			0
Amortization	(7)		(29)
Foreign currency translation	0		0
Ending balance	$ 115		$ 122

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

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