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) - USD ($) $ in Millions	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Finite-lived Intangible Assets [Roll Forward]
Beginning balance			$ 1,320	$ 1,544	$ 1,544
Amortization	$ (56)	$ (60)	(176)	(180)	(239)
Acquisitions			20
Foreign currency translation			2		15
Ending balance	1,166		1,166		1,320
Investment Servicing
Finite-lived Intangible Assets [Roll Forward]
Beginning balance			1,293	1,495	1,495
Amortization			(164)		(217)
Acquisitions			7
Foreign currency translation			2		15
Ending balance	1,138		1,138		1,293
Investment Management
Finite-lived Intangible Assets [Roll Forward]
Beginning balance			27	$ 49	49
Amortization			(12)		(22)
Acquisitions			13
Foreign currency translation			0		0
Ending balance	$ 28		$ 28		$ 27