Contingent Liabilities and Guarantees - Guarantees (Details) $ in Millions	Sep. 30, 2022 USD ($)
Guarantor Obligations [Line Items]
Maximum Potential Undiscounted Future Payments	$ 18,304
Liability Recorded	375
Written put options
Guarantor Obligations [Line Items]
Maximum Potential Undiscounted Future Payments	3,883
Liability Recorded	251
Standby letters of credit
Guarantor Obligations [Line Items]
Maximum Potential Undiscounted Future Payments	4,473
Liability Recorded	84
Recourse agreement with FNMA
Guarantor Obligations [Line Items]
Maximum Potential Undiscounted Future Payments	6,650
Liability Recorded	26
Residential mortgage reserve
Guarantor Obligations [Line Items]
Maximum Potential Undiscounted Future Payments	3,298
Liability Recorded	$ 14

The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (c)
-URI https://asc.fasb.org/extlink&oid=124440162&loc=d3e12069-110248

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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.

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- Definition

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-URI https://asc.fasb.org/extlink&oid=124440162&loc=d3e12069-110248

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