Goodwill and Other Intangible Assets - Changes in the Carrying Amount of Other Intangible Assets (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Mar. 31, 2025	Mar. 31, 2024	Jun. 30, 2024
Finite-lived Intangible Assets [Roll Forward]
Beginning balance	$ 1,089	$ 1,320	$ 1,320
Acquisitions			20
Amortization	(54)	(60)	(230)
Foreign currency translation	11		(21)
Ending balance	1,046
Investment Servicing
Finite-lived Intangible Assets [Roll Forward]
Beginning balance	1,063	1,293	1,293
Acquisitions			7
Amortization	(53)		(216)
Foreign currency translation	11		(21)
Ending balance	1,021
Investment Management
Finite-lived Intangible Assets [Roll Forward]
Beginning balance	26	$ 27	27
Acquisitions			13
Amortization	(1)		(14)
Foreign currency translation	0		$ 0
Ending balance	$ 25

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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- Definition

Amount of foreign currency translation gain (loss) which increases (decreases) assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

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- Definition

Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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Amount of increase (decrease) to assets, excluding financial assets and goodwill, lacking physical substance with a finite life for purchase accounting adjustments.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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