Sales of Receivables and Servicing Rights - Activity Related to the MSR Portfolio (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Transfers and Servicing [Abstract]
Securities (losses) gains, net - non-qualifying hedges on mortgage servicing rights	$ (2)	$ (2)	$ 2
Changes in fair value and settlement of free-standing derivatives purchased to economically hedge the MSR portfolio	(363)	(123)	307
MSR fair value adjustments due to changes in inputs or assumptions	$ 355	$ 142	$ (311)

Amount of unrealized and realized gain (loss) on investment in debt security measured at fair value with change in fair value recognized in net income (trading).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 14
-URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27476-111563

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Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4CC
-URI https://asc.fasb.org/extlink&oid=125515794&loc=SL109998890-113959

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (e)
-URI https://asc.fasb.org/extlink&oid=125515794&loc=SL5624171-113959

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- Definition

Amount of increase (decrease) in fair value from changes in the inputs, assumptions, or model used to calculate the fair value of the contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 50
-Section 50
-Paragraph 3
-Subparagraph (a)(4)(i)
-URI https://asc.fasb.org/extlink&oid=128311188&loc=d3e122625-111746

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