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, 2019	Mar. 31, 2018	Dec. 31, 2018
Finite-lived Intangible Assets [Roll Forward]
Beginning balance	$ 2,369	$ 1,613	$ 1,613
Acquisitions			1,007
Acquisitions	(93)
Amortization	(60)	(50)	(226)
Foreign currency translation	(8)		(25)
Ending balance	2,208		2,369
Investment Servicing
Finite-lived Intangible Assets [Roll Forward]
Beginning balance	2,218	1,432	1,432
Acquisitions			1,007
Acquisitions	(93)
Amortization	(53)		(196)
Foreign currency translation	(8)		(25)
Ending balance	2,064		2,218
Investment Management
Finite-lived Intangible Assets [Roll Forward]
Beginning balance	151	$ 181	181
Acquisitions			0
Acquisitions	0
Amortization	(7)		(30)
Foreign currency translation	0		0
Ending balance	144		$ 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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Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition.

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