Contingent Liabilities and Guarantees - Guarantees (Details) $ in Millions	Jun. 30, 2020 USD ($)
Guarantor Obligations [Line Items]
Maximum Potential Undiscounted Future Payments	$ 13,844
Liability Recorded	183
Written put options
Guarantor Obligations [Line Items]
Maximum Potential Undiscounted Future Payments	3,276
Liability Recorded	84
Standby letters of credit
Guarantor Obligations [Line Items]
Maximum Potential Undiscounted Future Payments	3,048
Liability Recorded	69
Recourse agreement with FNMA
Guarantor Obligations [Line Items]
Maximum Potential Undiscounted Future Payments	5,463
Liability Recorded	22
Residential mortgage reserve
Guarantor Obligations [Line Items]
Maximum Potential Undiscounted Future Payments	2,057
Liability Recorded	$ 8

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=121555522&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=121555522&loc=d3e12069-110248

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