v3.26.1
COMMITMENTS, CONTINGENCIES AND OFF-BALANCE-SHEET ACTIVITIES - NARRATIVE (Details)
$ in Millions
Jun. 05, 2026
USD ($)
Sep. 29, 2025
plaintiff
Jun. 30, 2026
USD ($)
security
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]      
Available securities used as collateral for securities loaned     $ 194.7
Available securities used as collateral for bank loans     161.6
Available securities used as collateral for OCC margin requirements     55.0
Available securities used as collateral for OCC margin requirements     $ 40.0
Number of pending punitive class action lawsuits | security     3
Number of plaintiffs | plaintiff   6  
FINRA Arbitration      
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]      
Loss contingency, damages sought, value $ 49.0    
Loss contingency accrual     $ 21.0
Provision for credit losses - unfunded lending commitments | Low Income Housing Tax Credits      
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]      
Commitments to contribute capital     $ 53.2