Loans - Contractual Maturity of Loans Outstanding by Repricing Characteristic (Details) $ in Millions	Dec. 31, 2023 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Receivables at Predetermined Interest Rates	$ 6,279
Receivables at Floating or Adjustable Rates	36,176
Total Loans Due After One Year	42,455
Real estate, including construction \| Commercial loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Receivables at Predetermined Interest Rates	141
Receivables at Floating or Adjustable Rates	4,063
Total Loans Due After One Year	4,204
Business and corporate banking \| Commercial loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Receivables at Predetermined Interest Rates	312
Receivables at Floating or Adjustable Rates	9,014
Total Loans Due After One Year	9,326
Global banking \| Commercial loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Receivables at Predetermined Interest Rates	213
Receivables at Floating or Adjustable Rates	6,148
Total Loans Due After One Year	6,361
Other commercial \| Commercial loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Receivables at Predetermined Interest Rates	128
Receivables at Floating or Adjustable Rates	3,681
Total Loans Due After One Year	3,809
Residential mortgages \| Consumer loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Receivables at Predetermined Interest Rates	5,471
Receivables at Floating or Adjustable Rates	12,813
Total Loans Due After One Year	18,284
Home equity mortgages \| Consumer loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Receivables at Predetermined Interest Rates	14
Receivables at Floating or Adjustable Rates	230
Total Loans Due After One Year	244
Credit cards \| Consumer loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Receivables at Predetermined Interest Rates	0
Receivables at Floating or Adjustable Rates	199
Total Loans Due After One Year	199
Other consumer \| Consumer loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Receivables at Predetermined Interest Rates	0
Receivables at Floating or Adjustable Rates	28
Total Loans Due After One Year	$ 28

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

No definition available.

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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

No definition available.

+ Details

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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

+ Details

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