Contingent Liabilities and Guarantees - Guarantees (Details) $ in Millions	Jun. 30, 2021 USD ($)
Guarantor Obligations [Line Items]
Maximum Potential Undiscounted Future Payments	$ 15,909
Liability Recorded	142
Written put options
Guarantor Obligations [Line Items]
Maximum Potential Undiscounted Future Payments	3,756
Liability Recorded	34
Standby letters of credit
Guarantor Obligations [Line Items]
Maximum Potential Undiscounted Future Payments	3,304
Liability Recorded	72
Recourse agreement with FNMA
Guarantor Obligations [Line Items]
Maximum Potential Undiscounted Future Payments	5,999
Liability Recorded	24
Residential mortgage reserve
Guarantor Obligations [Line Items]
Maximum Potential Undiscounted Future Payments	2,850
Liability Recorded	$ 12

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 http://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 http://asc.fasb.org/extlink&oid=124440162&loc=d3e12069-110248

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