v3.26.1
Loans and Allowance for Loan Losses - Schedule of Amortized Cost of FDM Loans by Loan Portfolio Class (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 [Line Items]        
Amortized cost of loans, modified $ 104 $ 38 $ 132 $ 42
Percentage of Total by Financing Class 0.10% 0.10% 0.20% 0.10%
Interest Rate Reduction        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified $ 0 $ 0 $ 0 $ 0
Term Extension        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified 40 4 55 8
Payment Delay        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified 30   43  
Payment Deferral and Term Extension        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified 34 34 34 34
Total commercial and industrial        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified $ 67 $ 4 $ 81 $ 8
Percentage of Total by Financing Class 0.10% 0.00% 0.20% 0.00%
Total commercial and industrial | Interest Rate Reduction        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified $ 0 $ 0 $ 0 $ 0
Total commercial and industrial | Term Extension        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified 40 4 54 8
Total commercial and industrial | Payment Delay        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified 27   27  
Total commercial and industrial | Payment Deferral and Term Extension        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified 0 0 0 0
Total commercial and industrial | Commercial, financial and agricultural        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified $ 67 $ 4 $ 79 $ 8
Percentage of Total by Financing Class 0.20% 0.00% 0.20% 0.10%
Total commercial and industrial | Commercial, financial and agricultural | Interest Rate Reduction        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified $ 0 $ 0 $ 0 $ 0
Total commercial and industrial | Commercial, financial and agricultural | Term Extension        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified 40 4 52 8
Total commercial and industrial | Commercial, financial and agricultural | Payment Delay        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified 27   27  
Total commercial and industrial | Commercial, financial and agricultural | Payment Deferral and Term Extension        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified 0 0 0 0
Total commercial and industrial | Owner-occupied        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified     $ 2  
Percentage of Total by Financing Class     0.00%  
Total commercial and industrial | Owner-occupied | Interest Rate Reduction        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified     $ 0  
Total commercial and industrial | Owner-occupied | Term Extension        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified     2  
Total commercial and industrial | Owner-occupied | Payment Delay        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified     0  
Total commercial and industrial | Owner-occupied | Payment Deferral and Term Extension        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified     0  
Total commercial real estate        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified $ 34 $ 34 $ 44 $ 34
Percentage of Total by Financing Class 0.10% 0.30% 0.20% 0.30%
Total commercial real estate | Interest Rate Reduction        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified $ 0 $ 0 $ 0 $ 0
Total commercial real estate | Term Extension        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified 0 0 0 0
Total commercial real estate | Payment Delay        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified 0   10  
Total commercial real estate | Payment Deferral and Term Extension        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified 34 34 34 34
Total commercial real estate | Investment properties        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified $ 34 $ 34 $ 44 $ 34
Percentage of Total by Financing Class 0.20% 0.30% 0.20% 0.30%
Total commercial real estate | Investment properties | Interest Rate Reduction        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified $ 0 $ 0 $ 0
Total commercial real estate | Investment properties | Term Extension        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified 0 0 0 0
Total commercial real estate | Investment properties | Payment Delay        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified 0   10  
Total commercial real estate | Investment properties | Payment Deferral and Term Extension        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified 34 $ 34 34 $ 34
Total consumer        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified $ 3   $ 7  
Percentage of Total by Financing Class 0.00%   0.10%  
Total consumer | Interest Rate Reduction        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified $ 0   $ 0  
Total consumer | Term Extension        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified 0   1  
Total consumer | Payment Delay        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified 3   6  
Total consumer | Payment Deferral and Term Extension        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified 0   0  
Total consumer | Consumer mortgages        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified $ 3   $ 6  
Percentage of Total by Financing Class 0.00%   0.10%  
Total consumer | Consumer mortgages | Interest Rate Reduction        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified $ 0   $ 0  
Total consumer | Consumer mortgages | Term Extension        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified 0   0  
Total consumer | Consumer mortgages | Payment Delay        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified 3   6  
Total consumer | Consumer mortgages | Payment Deferral and Term Extension        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified $ 0   0  
Total consumer | Other consumer loans        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified     $ 1  
Percentage of Total by Financing Class     0.10%  
Total consumer | Other consumer loans | Interest Rate Reduction        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified     $ 0  
Total consumer | Other consumer loans | Term Extension        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified     1  
Total consumer | Other consumer loans | Payment Delay        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified     0  
Total consumer | Other consumer loans | Payment Deferral and Term Extension        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified     $ 0