v3.26.1
FAIR VALUE MEASUREMENTS - Schedule of Non-Recurring Basis Assets (Details) - USD ($)
$ in Millions
Mar. 31, 2026
Dec. 31, 2025
Mar. 31, 2025
Dec. 31, 2024
Mortgage Servicing Rights        
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]        
Other assets $ 91.8 $ 88.2 $ 84.8 $ 86.3
Level 1        
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]        
Other assets 0.0 0.0    
Level 2        
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]        
Other assets 0.0 0.0    
Level 3        
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]        
Other assets 94.0 90.0    
Fair Value, Nonrecurring        
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]        
Collateral dependent loans 92.0 126.0    
Other real estate owned   1.0    
Fair Value, Nonrecurring | SBA-Guaranteed Loan Servicing        
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]        
Other assets 2.0 2.0    
Fair Value, Nonrecurring | Mortgage Servicing Rights        
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]        
Other assets   2.0    
Fair Value, Nonrecurring | Level 1        
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]        
Collateral dependent loans 0.0 0.0    
Other real estate owned   0.0    
Fair Value, Nonrecurring | Level 1 | SBA-Guaranteed Loan Servicing        
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]        
Other assets 0.0 0.0    
Fair Value, Nonrecurring | Level 1 | Mortgage Servicing Rights        
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]        
Other assets   0.0    
Fair Value, Nonrecurring | Level 2        
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]        
Collateral dependent loans 0.0 0.0    
Other real estate owned   0.0    
Fair Value, Nonrecurring | Level 2 | SBA-Guaranteed Loan Servicing        
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]        
Other assets 0.0 0.0    
Fair Value, Nonrecurring | Level 2 | Mortgage Servicing Rights        
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]        
Other assets   0.0    
Fair Value, Nonrecurring | Level 3        
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]        
Collateral dependent loans 92.0 126.0    
Other real estate owned   1.0    
Fair Value, Nonrecurring | Level 3 | SBA-Guaranteed Loan Servicing        
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]        
Other assets $ 2.0 2.0    
Fair Value, Nonrecurring | Level 3 | Mortgage Servicing Rights        
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]        
Other assets   $ 2.0