Goodwill and Other Intangible Assets - Changes in the Carrying Amount of Other Intangible Assets (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Finite-lived Intangible Assets [Roll Forward]
Beginning balance	$ 1,544	$ 1,816
Amortization	(239)	(238)	$ (245)
Foreign currency translation	15	(34)
Ending balance	1,320	1,544	1,816
Investment Servicing
Finite-lived Intangible Assets [Roll Forward]
Beginning balance	1,495	1,746
Amortization	(217)	(217)
Foreign currency translation	15	(34)
Ending balance	1,293	1,495	1,746
Investment Management
Finite-lived Intangible Assets [Roll Forward]
Beginning balance	49	70
Amortization	(22)	(21)
Foreign currency translation	0	0
Ending balance	$ 27	$ 49	$ 70

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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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 926
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-Name Accounting Standards Codification
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