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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, 2024	Mar. 31, 2023
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Change in estimated partner reimbursements that decreased provision for credit losses	$ 2,683	$ 2,795
Loss sharing agreements
Financing Receivable, Allowance for Credit Loss [Roll Forward]
Estimated reimbursements from partners, beginning of period	2,014	1,558
Amounts due from partners for charged off loans	(324)	(201)
Change in estimated partner reimbursements that decreased provision for credit losses	385	484
Estimated reimbursements from partners, end of period	$ 2,075	$ 1,841

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/exampleRef
-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

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-Topic 326
-SubTopic 20
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