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Commitments, Contingencies, Guarantees and Others - Other Contingencies (Details) - FDIC Special Assessment - USD ($) $ in Millions	6 Months Ended	11 Months Ended
	Jun. 30, 2025	Sep. 30, 2024	Jul. 08, 2025
Loss Contingencies [Line Items]
Operating expenses	$ 325	$ 289
Subsequent Event
Loss Contingencies [Line Items]
Special assessment fees			$ 200

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Special Assessment Fees

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Generally recurring costs associated with normal operations except for the portion of these expenses which can be clearly related to production and included in cost of sales or services. Includes selling, general and administrative expense.

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