Loans - Contractual Maturity of Loans Outstanding by Repricing Characteristic (Details) $ in Billions	Dec. 31, 2025 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, before Allowance for Credit Loss, Predetermined Interest Rate, Maturity, after Year One	$ 5.9
Financing Receivable, before Allowance for Credit Loss, Adjustable Interest Rate, Maturity, after Year One	33.8
Financing Receivable, Before Allowance For Credit Loss, Maturity, Due After One Year	39.7
Real estate, including construction \| Commercial loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, before Allowance for Credit Loss, Predetermined Interest Rate, Maturity, after Year One	0.1
Financing Receivable, before Allowance for Credit Loss, Adjustable Interest Rate, Maturity, after Year One	2.3
Financing Receivable, Before Allowance For Credit Loss, Maturity, Due After One Year	2.4
Business and corporate banking \| Commercial loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, before Allowance for Credit Loss, Predetermined Interest Rate, Maturity, after Year One	0.5
Financing Receivable, before Allowance for Credit Loss, Adjustable Interest Rate, Maturity, after Year One	12.0
Financing Receivable, Before Allowance For Credit Loss, Maturity, Due After One Year	12.5
Other commercial \| Commercial loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, before Allowance for Credit Loss, Predetermined Interest Rate, Maturity, after Year One	0.2
Financing Receivable, before Allowance for Credit Loss, Adjustable Interest Rate, Maturity, after Year One	4.6
Financing Receivable, Before Allowance For Credit Loss, Maturity, Due After One Year	4.8
Residential mortgages \| Consumer loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, before Allowance for Credit Loss, Predetermined Interest Rate, Maturity, after Year One	5.1
Financing Receivable, before Allowance for Credit Loss, Adjustable Interest Rate, Maturity, after Year One	14.3
Financing Receivable, Before Allowance For Credit Loss, Maturity, Due After One Year	19.4
Other consumer \| Consumer loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable, before Allowance for Credit Loss, Predetermined Interest Rate, Maturity, after Year One	0.0
Financing Receivable, before Allowance for Credit Loss, Adjustable Interest Rate, Maturity, after Year One	0.6
Financing Receivable, Before Allowance For Credit Loss, Maturity, Due After One Year	$ 0.6

Financing Receivable, Before Allowance For Credit Loss, Maturity, Due After One Year

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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/2009/role/commonPracticeRef
-Topic 310
-SubTopic 20
-Name Accounting Standards Codification
-Section 40
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481628/310-20-40-7

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481990/310-10-45-2

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- Definition

Amount, before allowance for credit loss, of financing receivable with adjustable interest rate, maturing after next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-K (SK)
-Number 229
-Section 1404
-Paragraph b
-Subparagraph (2)
-Publisher SEC

+ Details

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- Definition

Amount, before allowance for credit loss, of financing receivable with predetermined interest rate, maturing after next fiscal year following current fiscal year. Excludes floating and adjustable rates and interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name Regulation S-K (SK)
-Number 229
-Section 1404
-Paragraph b
-Subparagraph (1)
-Publisher SEC

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