Loans, Lending Commitments and Related Allowance for Credit Losses - Gross Charge-offs by Origination Year (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Financing Receivable and Allowance for Credit Losses
Revolving	$ (39)		$ (39)	$ (30)
Two years ago	(18)		(18)
Three years ago			(2)
Four years ago		$ (1)	(11)	(2)
Five years ago		(39)		(69)
Prior	(44)		(85)
Prior				(40)
Total	(101)	(40)	(155)	(141)
Corporate
Financing Receivable and Allowance for Credit Losses
Revolving	(39)		(39)	(30)
Two years ago	0		0
Three years ago			0
Four years ago		0	0	0
Five years ago		0		0
Prior	0		0
Prior				0
Total	(39)	0	(39)	(30)
Secured lending facilities
Financing Receivable and Allowance for Credit Losses
Revolving	0		0	0
Two years ago	0		0
Three years ago			0
Four years ago		0	(11)	0
Five years ago		0		0
Prior	0		0
Prior				0
Total	0	0	(11)	0
Commercial real estate
Financing Receivable and Allowance for Credit Losses
Revolving	0		0	0
Two years ago	(18)		(18)
Three years ago			0
Four years ago		0	0	0
Five years ago		(39)		(68)
Prior	(44)		(85)
Prior				(40)
Total	(62)	(39)	(103)	(108)
Residential real estate
Financing Receivable and Allowance for Credit Losses
Revolving	0		0	0
Two years ago	0		0
Three years ago			0
Four years ago		0	0	0
Five years ago		0		0
Prior	0		0
Prior				0
Total	0	0	0	0
SBL and Other
Financing Receivable and Allowance for Credit Losses
Revolving	0		0	0
Two years ago	0		0
Three years ago			(2)
Four years ago		(1)	0	(2)
Five years ago		0		(1)
Prior	0		0
Prior				0
Total	$ 0	$ (1)	$ (2)	$ (3)

Financing Receivable, Allowance for Credit Loss, Writeoff

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- Definition

Financing Receivable, Originated, More than Six Years before Current Fiscal Year, Writeoff

+ References

No definition available.

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- Definition

Financing Receivable, Year Six, Originated, Five Years before Current Fiscal Year, Writeoff

+ References

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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
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph c
-Publisher SEC

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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Amount of writeoff of financing receivable originated more than five years before current fiscal year. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 79
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479294/326-20-55-79

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-6

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Amount of writeoff of financing receivable that can be withdrawn, repaid, and redrawn.

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- Definition

Amount of writeoff of financing receivable originated four years before current fiscal year. Excludes net investment in lease.

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- Definition

Amount of writeoff of financing receivable originated three years before current fiscal year. Excludes net investment in lease.

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Amount of writeoff of financing receivable originated two years before current fiscal year. Excludes net investment in lease.

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