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Allowance for Credit Losses and Reserve for Unfunded Lending Commitments - Summary of Loss Sharing Arrangements (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2025	Mar. 31, 2024
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Change in estimated partner reimbursements that decreased provision for credit losses	$ 2,369	$ 2,683
Allowance build (release) for credit losses	(359)
Loss sharing agreements
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Estimated reimbursements from partners, beginning of period	1,010	2,014
Amounts due from partners for charged off loans	(171)	(324)
Change in estimated partner reimbursements that decreased provision for credit losses	251	385
Estimated reimbursements from partners, end of period	$ 1,090	$ 2,075

X

- Definition

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

+ References

No definition available.

+ Details

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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.

+ References

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- Definition

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

+ References

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