Loan Receivables (Schedule of Accounts that Entered a Troubled Debt Restructuring Program) (Details) $ in Millions	12 Months Ended
Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($) accounts
Credit Card Loans [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Accounts that entered a loan modification program during the period, number of accounts \| accounts		237,339
Accounts that entered a loan modification program during the period, balances		$ 1,545
Financing Receivable, Revolving, Converted to Term Loan During Period	$ 408	$ 322
Total Other Loans [Member] \| Private Student Loans [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Accounts that entered a loan modification program during the period, number of accounts \| accounts		6,841
Accounts that entered a loan modification program during the period, balances		$ 127
Total Other Loans [Member] \| Personal Loans [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Accounts that entered a loan modification program during the period, number of accounts \| accounts		6,303
Accounts that entered a loan modification program during the period, balances		$ 86

The number of financing receivables that have been modified by troubled debt restructurings during the period.

No definition available.

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- Definition

The amount of outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings during the period.

+ References

No definition available.

+ Details

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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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-42

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
-Subparagraph (a)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-42

Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 12A
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481933/310-10-55-12A

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 33
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-33

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 34
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-34

+ Details

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- Definition

Amount of increase in term loan from conversion of revolving financing receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6A
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-6A

+ Details

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- Details

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- Details

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