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Allowance for Credit Losses and Reserve for Unfunded Lending Commitments - Summary of Loss Sharing Arrangements (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Financing Receivable, Credit Loss, Expense (Reversal)	$ (20,655)	$ (11,716)	$ (10,426)
Allowance build (release) for credit losses	7,200
Loss sharing agreements
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Estimated reimbursements from partners, beginning of period	1,010	2,014	1,558
Amounts due from partners for charged off loans	(657)	(904)	(980)
Financing Receivable, Credit Loss, Expense (Reversal)	(750)	100	(1,436)
Estimated reimbursements from partners, end of period	$ 1,103	$ 1,010	$ 2,014

X

- Definition

Loss Sharing Agreements, Financing Receivable, Allowance, Covered, Expected Reimbursement

+ References

No definition available.

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X

- Definition

Amount of increase (decrease) in allowance for credit loss on financing receivable.

+ References

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- Definition

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

+ References

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- Definition

Amount of writeoff of financing receivable, charged against allowance for credit loss.

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Amount of credit loss expense (reversal of expense) for financing receivable.

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