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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		9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Change in estimated partner reimbursements that (increased) decreased provision for credit losses	$ 2,714	$ 2,482	$ 16,513	$ 9,074
Loss sharing agreements
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Estimated reimbursements from partners, beginning of period	1,191	1,210	1,010	2,014
Amounts due from partners for charged off loans	(154)	(157)	(491)	(734)
Change in estimated partner reimbursements that (increased) decreased provision for credit losses	95	102	613	(125)
Estimated reimbursements from partners, end of period	$ 1,132	$ 1,155	$ 1,132	$ 1,155

X

- Definition

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

+ References

No definition available.

+ Details

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X

- Definition

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

+ References

No definition available.

+ Details

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X

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
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-Publisher FASB
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