v3.26.1
FAIR VALUE MEASUREMENTS - Schedule of Non-Recurring Basis Assets (Details) - USD ($)
$ in Millions
Jun. 30, 2026
Mar. 31, 2026
Dec. 31, 2025
Jun. 30, 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 $ 94.9 $ 91.8 $ 88.2 $ 85.5 $ 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 97.0   90.0      
Fair Value, Nonrecurring            
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]            
Collateral dependent loans 91.0   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 91.0   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