Commitments and contingent liabilities - Significant Industry Concentrations Related to Credit Exposure (Details) - USD ($) $ in Millions	Jun. 30, 2026	Dec. 31, 2025
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Loans	$ 88,741	$ 80,615
Financial institutions
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Loans	15,297	$ 13,309
Unfunded commitments	29,000
Total exposure	44,300
Financial institutions \| Securities industry
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Loans	4,100
Unfunded commitments	12,700
Total exposure	16,800
Financial institutions \| Banks
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Loans	8,600
Unfunded commitments	1,900
Total exposure	10,500
Financial institutions \| Asset managers
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Loans	1,900
Unfunded commitments	8,300
Total exposure	10,200
Financial institutions \| Insurance
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Loans	0
Unfunded commitments	4,300
Total exposure	4,300
Financial institutions \| Government
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Loans	0
Unfunded commitments	800
Total exposure	800
Financial institutions \| Other
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Loans	700
Unfunded commitments	1,000
Total exposure	1,700
Commercial
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Loans	1,800
Unfunded commitments	13,400
Total exposure	15,200
Commercial \| Manufacturing
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Loans	800
Unfunded commitments	4,400
Total exposure	5,200
Commercial \| Services and other
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Loans	900
Unfunded commitments	3,800
Total exposure	4,700
Commercial \| Energy and utilities
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Loans	100
Unfunded commitments	4,400
Total exposure	4,500
Commercial \| Media and telecom
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Loans	0
Unfunded commitments	800
Total exposure	$ 800

The sum of loans outstanding and unfunded credit commitments

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- Definition

Credit commitments to extend credit to a counterparty under certain terms and conditions.

+ 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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 11
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482907/825-10-50-11

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 825
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478898/942-825-50-1

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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/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

Reference 2: 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 3: 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

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