Loans, Lending Commitments and Related Allowance for Credit Losses - Allowance for Credit Losses Rollforward - Loans and Lending Commitments (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Allowance for loan losses rollforward
Beginning balance	$ 1,066	$ 1,169	$ 839
Gross charge-offs	(214)	(242)	(167)
Recoveries	22	7	2
Net (charge-offs)/recoveries	(192)	(235)	(165)
Provision (release)	230	146	488
Other	28	(14)	7
Ending balance	$ 1,132	$ 1,066	$ 1,169
Percent of loans to total loans	100.00%	100.00%	100.00%
Allowance for lending commitments rollforward
Beginning balance	$ 656	$ 551	$ 504
Provision (release)	119	118	44
Other	23	(13)	3
Ending balance	798	656	551
Total ending balance	1,930	1,722	1,720
Corporate
Allowance for loan losses rollforward
Beginning balance	200	241	235
Gross charge-offs	(24)	(39)	(34)
Recoveries	0	0	1
Net (charge-offs)/recoveries	(24)	(39)	(33)
Provision (release)	75	2	37
Other	9	(4)	2
Ending balance	$ 260	$ 200	$ 241
Percent of loans to total loans	3.00%	3.00%	3.00%
Allowance for lending commitments rollforward
Beginning balance	$ 507	$ 431	$ 411
Provision (release)	101	86	16
Other	17	(10)	4
Ending balance	625	507	431
Total ending balance	885	707	672
Secured lending facilities
Allowance for loan losses rollforward
Beginning balance	140	153	153
Gross charge-offs	0	(11)	0
Recoveries	0	0	0
Net (charge-offs)/recoveries	0	(11)	0
Provision (release)	59	1	0
Other	2	(3)	0
Ending balance	$ 201	$ 140	$ 153
Percent of loans to total loans	25.00%	22.00%	19.00%
Allowance for lending commitments rollforward
Beginning balance	$ 88	$ 70	$ 51
Provision (release)	46	19	18
Other	3	(1)	1
Ending balance	137	88	70
Total ending balance	338	228	223
Commercial real estate
Allowance for loan losses rollforward
Beginning balance	373	463	275
Gross charge-offs	(173)	(165)	(129)
Recoveries	22	4	0
Net (charge-offs)/recoveries	(151)	(161)	(129)
Provision (release)	47	77	314
Other	14	(6)	3
Ending balance	$ 283	$ 373	$ 463
Percent of loans to total loans	3.00%	4.00%	4.00%
Allowance for lending commitments rollforward
Beginning balance	$ 40	$ 26	$ 15
Provision (release)	(28)	16	11
Other	0	(2)	0
Ending balance	12	40	26
Total ending balance	295	413	489
Residential real estate
Allowance for loan losses rollforward
Beginning balance	97	100	87
Gross charge-offs	0	0	0
Recoveries	0	0	1
Net (charge-offs)/recoveries	0	0	1
Provision (release)	30	(3)	13
Other	0	0	(1)
Ending balance	$ 127	$ 97	$ 100
Percent of loans to total loans	27.00%	29.00%	30.00%
Allowance for lending commitments rollforward
Beginning balance	$ 4	$ 4	$ 4
Provision (release)	1	0	0
Other	0	0	0
Ending balance	5	4	4
Total ending balance	132	101	104
SBL and Other
Allowance for loan losses rollforward
Beginning balance	256	212	89
Gross charge-offs	(17)	(27)	(4)
Recoveries	0	3	0
Net (charge-offs)/recoveries	(17)	(24)	(4)
Provision (release)	19	69	124
Other	3	(1)	3
Ending balance	$ 261	$ 256	$ 212
Percent of loans to total loans	42.00%	42.00%	44.00%
Allowance for lending commitments rollforward
Beginning balance	$ 17	$ 20	$ 23
Provision (release)	(1)	(3)	(1)
Other	3	0	(2)
Ending balance	19	17	20
Total ending balance	$ 280	$ 273	$ 232

Allowance for Credit Loss and Exposures

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- Definition

Amount of other addition (reduction) in allowance reserve for credit loss.

+ References

No definition available.

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- Definition

Financing Receivable, Loans Held for Investment by Loan Type to Total Loans Held for Investment

+ References

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- Definition

A valuation allowance for credit exposures related to off-balance-sheet loan commitments.

+ References

No definition available.

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- Definition

Other increase (decrease) in the allowance for credit exposures on off-balance-sheet loan commitments.

+ References

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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No definition available.

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Amount excluding accrued interest, of allowance for credit loss on 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

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- Definition

Amount, excluding accrued interest, of increase in allowance for credit loss on financing receivable from recovery. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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- Definition

Amount, excluding accrued interest, of decrease in allowance for credit loss on financing receivable from writeoff. Excludes net investment in lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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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- Definition

Amount, excluding accrued interest, of decrease (increase) in allowance for credit loss on financing receivable from writeoff (recovery). Excludes net investment in lease.

+ References

Reference 1: 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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- Definition

Amount, excluding accrued interest, of credit loss expense (reversal of expense) on financing receivable. Excludes net investment in lease.

+ References

Reference 1: 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 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 220
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 22
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147476148/220-40-50-22

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- Definition

Amount of expense (reversal of expense) for expected credit loss for off-balance sheet credit exposure. Excludes off-balance sheet credit exposure accounted for as insurance and instrument accounted for under derivatives and hedging.

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