Goodwill and Other Intangible Assets - Changes In The Carrying Amount Of Other Intangible Assets (Details) € in Millions, $ in Millions	3 Months Ended	12 Months Ended
Mar. 31, 2021 USD ($)	Mar. 31, 2021 EUR (€)	Mar. 31, 2020 USD ($)	Dec. 31, 2020 USD ($)
Finite-lived Intangible Assets [Roll Forward]
Beginning balance	$ 1,827		$ 2,030	$ 2,030
Amortization	(58)		(58)	(234)
Foreign currency translation	(15)			31
Acquisitions	253
Ending balance	2,007			1,827
Investment Servicing
Finite-lived Intangible Assets [Roll Forward]
Beginning balance	1,733		1,908	1,908
Amortization	(52)			(206)
Foreign currency translation	(15)			31
Acquisitions	253
Ending balance	1,919			1,733
Investment Servicing \| Fideuram Bank Luxembour
Finite-lived Intangible Assets [Roll Forward]
Payments for acquisition	258	€ 220
Investment Management
Finite-lived Intangible Assets [Roll Forward]
Beginning balance	94		$ 122	122
Amortization	(6)			(28)
Foreign currency translation	0			0
Acquisitions	0
Ending balance	$ 88			$ 94

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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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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