Loans and ACL - Narrative (Details) $ in Millions	3 Months Ended
Mar. 31, 2023 USD ($)
Financing Receivable
Unfunded lending commitments related to the modified obligations	$ 353
Loan Restructuring, Trial Modifications, Amount	64
Commercial:
Financing Receivable
Allowance for Loan and Lease Losses, Period Increase (Decrease)	156
Consumer:
Financing Receivable
Allowance for Loan and Lease Losses, Period Increase (Decrease)	$ (49)

Amount of increase (decrease) of allowance reserve for credit loss.

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Amount of financing receivable modified on trial basis.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 33
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-33

+ Details

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- Definition

Amount of commitment to lend additional funds to debtor experiencing financial difficulty for which creditor has modified terms of financing receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 36
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-36

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-SubTopic 40
-Topic 310
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481746/310-40-50-1

+ Details

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- Details

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- Details

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