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, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024
Financing Receivable and Allowance for Credit Losses
Revolving	$ (8)	$ (39)	$ (8)	$ (39)
2025	(10)		(10)
2022	(2)	(18)	(13)	(18)
2021	(38)		(49)	(2)
Prior	(6)	(44)	(46)	(96)
Total	(64)	(101)	(126)	(155)
Corporate
Financing Receivable and Allowance for Credit Losses
Revolving	0	(39)	0	(39)
2025	(10)		(10)
2022	0	0	0	0
2021	0		0	0
Prior	0	0	0	0
Total	(10)	(39)	(10)	(39)
Secured lending facilities
Financing Receivable and Allowance for Credit Losses
Revolving	0	0	0	0
2025	0		0
2022	0	0	0	0
2021	0		0	0
Prior	0	0	0	(11)
Total	0	0	0	(11)
Commercial real estate
Financing Receivable and Allowance for Credit Losses
Revolving	0	0	0	0
2025	0		0
2022	(2)	(18)	(13)	(18)
2021	(34)		(45)	0
Prior	(1)	(44)	(41)	(85)
Total	(37)	(62)	(99)	(103)
Residential real estate
Financing Receivable and Allowance for Credit Losses
Revolving	0	0	0	0
2025	0		0
2022	0	0	0	0
2021	0		0	0
Prior	0	0	0	0
Total	0	0	0	0
SBL and Other
Financing Receivable and Allowance for Credit Losses
Revolving	(8)	0	(8)	0
2025	0		0
2022	0	0	0	0
2021	(4)			(2)
Prior	(5)	0	(4)	0
Total	$ (17)	$ 0	$ (17)	$ (2)

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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 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
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-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
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-Section 50
-Paragraph 13
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

Reference 7: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph c
-Publisher SEC

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

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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 in current fiscal year. Excludes net investment in lease.

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