Sales of Receivables and Servicing Rights - Activity Related to Mortgage Banking Net Revenue (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Transfers and Servicing [Abstract]
Contractually Specified Servicing Fee Income, Statement of Income or Comprehensive Income [Extensible Enumeration]	Fees and Commissions, Mortgage Banking and Servicing	Fees and Commissions, Mortgage Banking and Servicing	Fees and Commissions, Mortgage Banking and Servicing
Residential mortgage loan sales	$ 4,888	$ 13,307	$ 16,900
Origination fees and gains on loan sales	79	91	285
Gross mortgage servicing fees	$ 319	$ 310	$ 247

Indicates line item in statement of income or comprehensive income that includes contractually specified servicing fee income.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
-SubTopic 50
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481229/860-50-50-2

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- Definition

All amounts that, per contract, are due to the servicer in exchange for servicing the financial asset and would no longer be received by a servicer if the beneficial owners of the serviced assets (or their trustees or agents) were to exercise their actual or potential authority under the contract to shift the servicing to another servicer. Depending on the servicing contract, those fees may include some or all of the difference between the interest rate collected on the asset being serviced and the rate to be paid to the beneficial owners of the asset.

+ References

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- Definition

Amount of gain (loss) on sale of financing receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 860
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481326/860-20-50-5

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- Definition

The cash inflow from sales of loans that are secured with real estate mortgages and are held with the intention to resell in the near future.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482740/230-10-45-25

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 21
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482740/230-10-45-21

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- References

No definition available.

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