v3.26.1
CREDIT QUALITY AND THE ALLOWANCE FOR CREDIT LOSSES - Troubled Debt Restructurings, Modified Default (Details) - USD ($)
$ in Millions
 3 Months Ended 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default $ 126 $ 54 $ 187 $ 134
Interest Rate Reduction        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default 2 2 2 4
Term Extension        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default 123 43 179 117
Payment Delay        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default 1 4 1 5
Interest Rate Reduction and Term Extension        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default   3 3 6
Term Extension and Payment Delay        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default   2 1 2
Interest Rate Reduction, Term Extension, and Payment Delay        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default     1  
Commercial        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default 118 36 167 107
Commercial | Interest Rate Reduction        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default 0 0 0 0
Commercial | Term Extension        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default 118 32 167 103
Commercial | Payment Delay        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default 0 2 0 2
Commercial | Interest Rate Reduction and Term Extension        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default   0 0 0
Commercial | Term Extension and Payment Delay        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default   2 0 2
Commercial | Interest Rate Reduction, Term Extension, and Payment Delay        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default     0  
Commercial | Commercial and industrial        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default 83 28 83 29
Commercial | Commercial and industrial | Interest Rate Reduction        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default 0 0 0 0
Commercial | Commercial and industrial | Term Extension        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default 83 26 83 27
Commercial | Commercial and industrial | Payment Delay        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default 0 0 0 0
Commercial | Commercial and industrial | Interest Rate Reduction and Term Extension        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default   0 0 0
Commercial | Commercial and industrial | Term Extension and Payment Delay        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default   2 0 2
Commercial | Commercial and industrial | Interest Rate Reduction, Term Extension, and Payment Delay        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default     0  
Commercial | Commercial real estate        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default 35 8 84 78
Commercial | Commercial real estate | Interest Rate Reduction        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default 0 0 0 0
Commercial | Commercial real estate | Term Extension        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default 35 6 84 76
Commercial | Commercial real estate | Payment Delay        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default 0 2 0 2
Commercial | Commercial real estate | Interest Rate Reduction and Term Extension        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default   0 0 0
Commercial | Commercial real estate | Term Extension and Payment Delay        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default   0 0 0
Commercial | Commercial real estate | Interest Rate Reduction, Term Extension, and Payment Delay        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default     0  
Retail        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default 8 18 20 27
Retail | Interest Rate Reduction        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default 2 2 2 4
Retail | Term Extension        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default 5 11 12 14
Retail | Payment Delay        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default 1 2 1 3
Retail | Interest Rate Reduction and Term Extension        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default   3 3 6
Retail | Term Extension and Payment Delay        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default   0 1 0
Retail | Interest Rate Reduction, Term Extension, and Payment Delay        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default     1  
Retail | Residential mortgages        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default 6 16 17 22
Retail | Residential mortgages | Interest Rate Reduction        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default 0 1 0 1
Retail | Residential mortgages | Term Extension        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default 5 11 12 14
Retail | Residential mortgages | Payment Delay        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default 1 1 1 2
Retail | Residential mortgages | Interest Rate Reduction and Term Extension        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default   3 2 5
Retail | Residential mortgages | Term Extension and Payment Delay        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default   0 1 0
Retail | Residential mortgages | Interest Rate Reduction, Term Extension, and Payment Delay        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default     1  
Retail | Home equity        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default 0 1 1 3
Retail | Home equity | Interest Rate Reduction        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default 0 0 0 1
Retail | Home equity | Term Extension        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default 0 0 0 0
Retail | Home equity | Payment Delay        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default 0 1 0 1
Retail | Home equity | Interest Rate Reduction and Term Extension        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default   0 1 1
Retail | Home equity | Term Extension and Payment Delay        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default   0 0 0
Retail | Home equity | Interest Rate Reduction, Term Extension, and Payment Delay        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default     0  
Retail | Education        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default 1 0 1 1
Retail | Education | Interest Rate Reduction        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default 1 0 1 1
Retail | Education | Term Extension        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default 0 0 0 0
Retail | Education | Payment Delay        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default 0 0 0 0
Retail | Education | Interest Rate Reduction and Term Extension        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default   0 0 0
Retail | Education | Term Extension and Payment Delay        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default   0 0 0
Retail | Education | Interest Rate Reduction, Term Extension, and Payment Delay        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default     0  
Retail | Other retail        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default 1 1 1 1
Retail | Other retail | Interest Rate Reduction        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default 1 1 1 1
Retail | Other retail | Term Extension        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default 0 0 0 0
Retail | Other retail | Payment Delay        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default $ 0 0 0 0
Retail | Other retail | Interest Rate Reduction and Term Extension        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default   0 0 0
Retail | Other retail | Term Extension and Payment Delay        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default   $ 0 0 $ 0
Retail | Other retail | Interest Rate Reduction, Term Extension, and Payment Delay        
Financing Receivable, Modified, Subsequent Default [Line Items]        
Amortized cost basis of modified loans that are in subsequent default     $ 0