Loans - Loan Payment Modifications by Type of Modification (Details) $ in Millions	12 Months Ended
Dec. 31, 2023 USD ($)
Financing Receivable, Modified [Line Items]
Loans modified	$ 628
% of Total Loans	1.10%
Commercial loans
Financing Receivable, Modified [Line Items]
Loans modified	$ 616
% of Total Loans	1.50%
Commercial loans \| Real estate, including construction
Financing Receivable, Modified [Line Items]
Loans modified	$ 168
% of Total Loans	2.40%
Commercial loans \| Business and corporate banking
Financing Receivable, Modified [Line Items]
Loans modified	$ 398
% of Total Loans	2.50%
Loan with payment modification subsequently charged-off	$ 32
Commercial loans \| Global banking
Financing Receivable, Modified [Line Items]
Loans modified	$ 50
% of Total Loans	0.50%
Consumer loans
Financing Receivable, Modified [Line Items]
Loans modified	$ 12
% of Total Loans	0.10%
Consumer loans \| Residential mortgages
Financing Receivable, Modified [Line Items]
Loans modified	$ 12
% of Total Loans	0.10%
Interest Rate Reduction
Financing Receivable, Modified [Line Items]
Loans modified	$ 21
Interest Rate Reduction \| Commercial loans
Financing Receivable, Modified [Line Items]
Loans modified	21
Interest Rate Reduction \| Commercial loans \| Real estate, including construction
Financing Receivable, Modified [Line Items]
Loans modified	0
Interest Rate Reduction \| Commercial loans \| Business and corporate banking
Financing Receivable, Modified [Line Items]
Loans modified	0
Interest Rate Reduction \| Commercial loans \| Global banking
Financing Receivable, Modified [Line Items]
Loans modified	21
Interest Rate Reduction \| Consumer loans
Financing Receivable, Modified [Line Items]
Loans modified	0
Interest Rate Reduction \| Consumer loans \| Residential mortgages
Financing Receivable, Modified [Line Items]
Loans modified	0
Principal Forgiveness
Financing Receivable, Modified [Line Items]
Loans modified	0
Principal Forgiveness \| Commercial loans
Financing Receivable, Modified [Line Items]
Loans modified	0
Principal Forgiveness \| Commercial loans \| Real estate, including construction
Financing Receivable, Modified [Line Items]
Loans modified	0
Principal Forgiveness \| Commercial loans \| Business and corporate banking
Financing Receivable, Modified [Line Items]
Loans modified	0
Principal Forgiveness \| Commercial loans \| Global banking
Financing Receivable, Modified [Line Items]
Loans modified	0
Principal Forgiveness \| Consumer loans
Financing Receivable, Modified [Line Items]
Loans modified	0
Principal Forgiveness \| Consumer loans \| Residential mortgages
Financing Receivable, Modified [Line Items]
Loans modified	0
Term Extension / Significant Payment Deferral
Financing Receivable, Modified [Line Items]
Loans modified	418
Term Extension / Significant Payment Deferral \| Commercial loans
Financing Receivable, Modified [Line Items]
Loans modified	408
Term Extension / Significant Payment Deferral \| Commercial loans \| Real estate, including construction
Financing Receivable, Modified [Line Items]
Loans modified	168
Term Extension / Significant Payment Deferral \| Commercial loans \| Business and corporate banking
Financing Receivable, Modified [Line Items]
Loans modified	211
Term Extension / Significant Payment Deferral \| Commercial loans \| Global banking
Financing Receivable, Modified [Line Items]
Loans modified	29
Term Extension / Significant Payment Deferral \| Consumer loans
Financing Receivable, Modified [Line Items]
Loans modified	10
Term Extension / Significant Payment Deferral \| Consumer loans \| Residential mortgages
Financing Receivable, Modified [Line Items]
Loans modified	10
Combination
Financing Receivable, Modified [Line Items]
Loans modified	189
Combination \| Commercial loans
Financing Receivable, Modified [Line Items]
Loans modified	187
Combination \| Commercial loans \| Real estate, including construction
Financing Receivable, Modified [Line Items]
Loans modified	0
Combination \| Commercial loans \| Business and corporate banking
Financing Receivable, Modified [Line Items]
Loans modified	187
Combination \| Commercial loans \| Global banking
Financing Receivable, Modified [Line Items]
Loans modified	0
Combination \| Consumer loans
Financing Receivable, Modified [Line Items]
Loans modified	2
Combination \| Consumer loans \| Residential mortgages
Financing Receivable, Modified [Line Items]
Loans modified	$ 2

Financing Receivable, Excluding Accrued Interest, Modified, Subsequent Writeoff

No definition available.

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- Definition

Amortized cost excluding accrued interest, of financing receivable modified during period for debtor experiencing financial difficulty.

+ References

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- Definition

Percentage, excluding accrued interest, of financing receivable modified during period for debtor experiencing financial difficulty to total financing receivables.

+ References

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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

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