Bank Loans and Related Allowance for Credit Losses - Convert to Amortizing Loans (Details) - Residential real estate - HELOCs - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2024	Sep. 30, 2024	Dec. 31, 2023
Accounts, Notes, Loans and Financing Receivable [Line Items]
Converted to an amortizing loan by period end	$ 143	$ 143
Within 1 year	16	16
> 1 year – 3 years	38	38
> 3 years – 5 years	35	35
> 5 years	203	203
Total loans	435	435	$ 479
Converted to amortizing loans during the period	$ 4	$ 9

Financing Receivable, Convert To Amortizing Loans During Period

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- Definition

Financing Receivable, Revolving, Converted To Term Loan During Remainder Of Fiscal Year

+ References

No definition available.

+ Details

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- Definition

Financing Receivable, Revolving, Converted To Term Loan, Year Five And Thereafter

+ References

No definition available.

+ Details

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- Definition

Financing Receivable, Revolving, Converted To Term Loan, Year One

+ References

No definition available.

+ Details

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- Definition

Financing Receivable, Revolving, Converted To Term Loan, Year One To Year Three

+ References

No definition available.

+ Details

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- Definition

Financing Receivable, Revolving, Converted To Term Loan, Year Three To Year Five

+ 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

No definition available.

+ Details

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- Definition

Amortized cost excluding accrued interest, before allowance for credit loss, of financing receivable. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479344/326-20-45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 3B
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-3B

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479319/326-20-50-5

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- Details

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