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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Goodwill and Other Intangible Assets - Changes In The Carrying Amount Of Other Intangible Assets (Details) € in Millions, $ in Millions	3 Months Ended		6 Months Ended			12 Months Ended
	Jun. 30, 2021 USD ($)	Jun. 30, 2020 USD ($)	Jun. 30, 2021 USD ($)	Jun. 30, 2021 EUR (€)	Jun. 30, 2020 USD ($)	Dec. 31, 2020 USD ($)
Finite-lived Intangible Assets [Roll Forward]
Beginning balance			$ 1,827		$ 2,030	$ 2,030
Amortization	$ (63)	$ (58)	(121)		(116)	(234)
Foreign currency translation			(6)			31
Acquisitions			233
Ending balance	1,933		1,933			1,827
Investment Servicing
Finite-lived Intangible Assets [Roll Forward]
Beginning balance			1,733		1,908	1,908
Amortization			(108)			(206)
Foreign currency translation			(6)			31
Acquisitions			233
Ending balance	1,852		1,852			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			(13)			(28)
Foreign currency translation			0			0
Acquisitions			0
Ending balance	$ 81		$ 81			$ 94