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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Goodwill and Other Intangible Assets - Changes In The Carrying Amount Of Other Intangible Assets (Details) - USD ($) $ in Millions	3 Months Ended			9 Months Ended		12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Mar. 31, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Finite-lived Intangible Assets [Roll Forward]
Beginning balance			$ 2,369	$ 2,030	$ 2,369	$ 2,369
Acquisitions						(93)
Amortization	$ (59)	$ (59)		(175)	(178)	(236)
Foreign currency translation				15		(10)
Ending balance	1,870			1,870		2,030
Investment Servicing
Finite-lived Intangible Assets [Roll Forward]
Beginning balance			2,218	1,908	2,218	2,218
Acquisitions			(93)			(93)
Amortization				(154)		(207)
Foreign currency translation				15		(10)
Ending balance	1,769			1,769		1,908
Investment Management
Finite-lived Intangible Assets [Roll Forward]
Beginning balance			$ 151	122	$ 151	151
Acquisitions						0
Amortization				(21)		(29)
Foreign currency translation				0		0
Ending balance	$ 101			$ 101		$ 122