v3.26.3
Loans and Allowance for Loan Losses - Schedule of Amortized Cost of FDM Loans by Loan Portfolio Class (Details) - USD ($)
$ in Millions
 3 Months Ended 9 Months Ended
Sep. 30, 2026
Sep. 30, 2025
Sep. 30, 2026
Sep. 30, 2025
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified $ 64 $ 7 $ 186 $ 41
Percentage of Total by Financing Class 0.10% 0.00% 0.20% 0.10%
Term Extension        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified $ 37 $ 6 $ 90 $ 6
Payment Delay        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified 7   49  
Interest Rate Reduction and Term Extension        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified 20   20  
Payment Deferral and Term Extension        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified 0 1 27 35
Total commercial and industrial        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified $ 56 $ 7 $ 134 $ 7
Percentage of Total by Financing Class 0.10% 0.00% 0.30% 0.00%
Total commercial and industrial | Term Extension        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified $ 36 $ 6 $ 88 $ 6
Total commercial and industrial | Payment Delay        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified 0   26  
Total commercial and industrial | Interest Rate Reduction and Term Extension        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified 20   20  
Total commercial and industrial | Payment Deferral and Term Extension        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified 0 1 0 1
Total commercial and industrial | Commercial, financial and agricultural        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified $ 56 $ 7 $ 134 $ 7
Percentage of Total by Financing Class 0.10% 0.00% 0.40% 0.00%
Total commercial and industrial | Commercial, financial and agricultural | Term Extension        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified $ 36 $ 6 $ 88 $ 6
Total commercial and industrial | Commercial, financial and agricultural | Payment Delay        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified 0   26  
Total commercial and industrial | Commercial, financial and agricultural | Interest Rate Reduction and Term Extension        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified 20   20  
Total commercial and industrial | Commercial, financial and agricultural | Payment Deferral and Term Extension        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified 0 $ 1 0 1
Total commercial real estate        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified $ 0   $ 36 $ 34
Percentage of Total by Financing Class 0.00%   0.10% 0.30%
Total commercial real estate | Term Extension        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified $ 0   $ 0 $ 0
Total commercial real estate | Payment Delay        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified 0   9  
Total commercial real estate | Interest Rate Reduction and Term Extension        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified 0   0  
Total commercial real estate | Payment Deferral and Term Extension        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified 0   27 34
Total commercial real estate | Investment properties        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified $ 0   $ 36 $ 34
Percentage of Total by Financing Class 0.00%   0.20% 0.40%
Total commercial real estate | Investment properties | Term Extension        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified $ 0   $ 0 $ 0
Total commercial real estate | Investment properties | Payment Delay        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified 0   9  
Total commercial real estate | Investment properties | Interest Rate Reduction and Term Extension        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified 0   0  
Total commercial real estate | Investment properties | Payment Deferral and Term Extension        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified 0   27 $ 34
Total consumer        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified $ 8   $ 16  
Percentage of Total by Financing Class 0.10%   0.10%  
Total consumer | Term Extension        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified $ 1   $ 2  
Total consumer | Payment Delay        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified 7   14  
Total consumer | Interest Rate Reduction and Term Extension        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified 0   0  
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 $ 7   $ 14  
Percentage of Total by Financing Class 0.10%   0.20%  
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 7   14  
Total consumer | Consumer mortgages | Interest Rate Reduction and Term Extension        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified 0   0  
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   $ 2  
Percentage of Total by Financing Class 0.10%   0.10%  
Total consumer | Other consumer loans | Term Extension        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified $ 1   $ 2  
Total consumer | Other consumer loans | Payment Delay        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified 0   0  
Total consumer | Other consumer loans | Interest Rate Reduction and Term Extension        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified 0   0  
Total consumer | Other consumer loans | Payment Deferral and Term Extension        
Financing Receivable, Modified [Line Items]        
Amortized cost of loans, modified $ 0   $ 0