v3.25.1
Loans - Summary of Past Due Status of Loans With Payment Modifications (Details) - USD ($)
$ in Millions
Mar. 31, 2025
Dec. 31, 2024
Financing Receivable, Past Due [Line Items]    
Modified loans, past due $ 403 $ 443
30 - 89 Days    
Financing Receivable, Past Due [Line Items]    
Modified loans, past due 0 1
90+ Days    
Financing Receivable, Past Due [Line Items]    
Modified loans, past due 29 29
Current    
Financing Receivable, Past Due [Line Items]    
Modified loans, past due 374 413
Commercial loans    
Financing Receivable, Past Due [Line Items]    
Modified loans, past due 398 438
Commercial loans | Real estate, including construction    
Financing Receivable, Past Due [Line Items]    
Modified loans, past due 236 232
Commercial loans | Business and corporate banking    
Financing Receivable, Past Due [Line Items]    
Modified loans, past due 162 206
Commercial loans | 30 - 89 Days    
Financing Receivable, Past Due [Line Items]    
Modified loans, past due 0 0
Commercial loans | 30 - 89 Days | Real estate, including construction    
Financing Receivable, Past Due [Line Items]    
Modified loans, past due 0 0
Commercial loans | 30 - 89 Days | Business and corporate banking    
Financing Receivable, Past Due [Line Items]    
Modified loans, past due 0 0
Commercial loans | 90+ Days    
Financing Receivable, Past Due [Line Items]    
Modified loans, past due 28 29
Commercial loans | 90+ Days | Real estate, including construction    
Financing Receivable, Past Due [Line Items]    
Modified loans, past due 0 0
Commercial loans | 90+ Days | Business and corporate banking    
Financing Receivable, Past Due [Line Items]    
Modified loans, past due 28 29
Commercial loans | Current    
Financing Receivable, Past Due [Line Items]    
Modified loans, past due 370 409
Commercial loans | Current | Real estate, including construction    
Financing Receivable, Past Due [Line Items]    
Modified loans, past due 236 232
Commercial loans | Current | Business and corporate banking    
Financing Receivable, Past Due [Line Items]    
Modified loans, past due 134 177
Consumer loans    
Financing Receivable, Past Due [Line Items]    
Modified loans, past due 5 5
Consumer loans | Residential mortgages    
Financing Receivable, Past Due [Line Items]    
Modified loans, past due 5 5
Consumer loans | 30 - 89 Days    
Financing Receivable, Past Due [Line Items]    
Modified loans, past due 0 1
Consumer loans | 30 - 89 Days | Residential mortgages    
Financing Receivable, Past Due [Line Items]    
Modified loans, past due 0 1
Consumer loans | 90+ Days    
Financing Receivable, Past Due [Line Items]    
Modified loans, past due 1 0
Consumer loans | 90+ Days | Residential mortgages    
Financing Receivable, Past Due [Line Items]    
Modified loans, past due 1 0
Consumer loans | Current    
Financing Receivable, Past Due [Line Items]    
Modified loans, past due 4 4
Consumer loans | Current | Residential mortgages    
Financing Receivable, Past Due [Line Items]    
Modified loans, past due $ 4 $ 4