Loans, Lending Commitments and Related Allowance for Credit Losses - Allowance for Credit Losses Rollforward - Loans and Lending Commitments (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Allowance for loan losses rollforward
Beginning balance			$ 1,132	$ 1,066
Gross charge-offs			(72)	(62)
Recoveries			2	20
Net (charge-offs)/ recoveries			(70)	(42)
Provision (release)	$ 110	$ 138	192	219
Other			(6)	28
Ending balance	$ 1,248	$ 1,271	$ 1,248	$ 1,271
Percent of loans to total loans	100.00%	100.00%	100.00%	100.00%
Allowance for lending commitments rollforward
Beginning balance			$ 798	$ 656
Provision (release)	$ (12)	$ 58	4	112
Other			(10)	22
Ending balance	792	790	792	790
Total ending balance	2,040	2,061	2,040	2,061
Corporate
Allowance for loan losses rollforward
Beginning balance			260	200
Gross charge-offs			(45)	0
Recoveries			0	0
Net (charge-offs)/ recoveries			(45)	0
Provision (release)			66	63
Other			(2)	8
Ending balance	$ 279	$ 271	$ 279	$ 271
Percent of loans to total loans	3.00%	3.00%	3.00%	3.00%
Allowance for lending commitments rollforward
Beginning balance			$ 625	$ 507
Provision (release)			24	83
Other			(9)	17
Ending balance	$ 640	$ 607	640	607
Total ending balance	919	878	919	878
Secured lending facilities
Allowance for loan losses rollforward
Beginning balance			201	140
Gross charge-offs			0	0
Recoveries			0	0
Net (charge-offs)/ recoveries			0	0
Provision (release)			43	30
Other			(2)	5
Ending balance	$ 242	$ 175	$ 242	$ 175
Percent of loans to total loans	25.00%	24.00%	25.00%	24.00%
Allowance for lending commitments rollforward
Beginning balance			$ 137	$ 88
Provision (release)			(20)	47
Other			(1)	3
Ending balance	$ 116	$ 138	116	138
Total ending balance	358	313	358	313
Commercial real estate
Allowance for loan losses rollforward
Beginning balance			283	373
Gross charge-offs			(17)	(62)
Recoveries			2	20
Net (charge-offs)/ recoveries			(15)	(42)
Provision (release)			46	52
Other			(2)	15
Ending balance	$ 312	$ 398	$ 312	$ 398
Percent of loans to total loans	3.00%	3.00%	3.00%	3.00%
Allowance for lending commitments rollforward
Beginning balance			$ 12	$ 40
Provision (release)			4	(21)
Other			0	1
Ending balance	$ 16	$ 20	16	20
Total ending balance	328	418	328	418
Residential real estate
Allowance for loan losses rollforward
Beginning balance			127	97
Gross charge-offs			0	0
Recoveries			0	0
Net (charge-offs)/ recoveries			0	0
Provision (release)			9	23
Other			0	0
Ending balance	$ 136	$ 120	$ 136	$ 120
Percent of loans to total loans	26.00%	28.00%	26.00%	28.00%
Allowance for lending commitments rollforward
Beginning balance			$ 5	$ 4
Provision (release)			0	0
Other			0	0
Ending balance	$ 5	$ 4	5	4
Total ending balance	141	124	141	124
SBL and Other
Allowance for loan losses rollforward
Beginning balance			261	256
Gross charge-offs			(10)	0
Recoveries			0	0
Net (charge-offs)/ recoveries			(10)	0
Provision (release)			28	51
Other			0	0
Ending balance	$ 279	$ 307	$ 279	$ 307
Percent of loans to total loans	43.00%	42.00%	43.00%	42.00%
Allowance for lending commitments rollforward
Beginning balance			$ 19	$ 17
Provision (release)			(4)	3
Other			0	1
Ending balance	$ 15	$ 21	15	21
Total ending balance	$ 294	$ 328	$ 294	$ 328

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

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- Definition

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

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

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

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-Topic 942
-SubTopic 210
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Amount, excluding accrued interest, of increase in allowance for credit loss on financing receivable from recovery. Excludes net investment in lease.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 20
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-Publisher FASB
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Amount, excluding accrued interest, of decrease in allowance for credit loss on financing receivable from writeoff. Excludes net investment in lease.

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

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

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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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