v3.25.2
Investments - Narrative (Details)
$ in Millions
Dec. 31, 2024
USD ($)
lot
Dec. 31, 2023
USD ($)
Debt Securities, Available-for-Sale [Line Items]    
Securities held as collateral, at fair value $ 28.0  
Unrealized loss position aged over 12 months, number of positions | lot 778  
Cash and Securities Segregated under Federal and Other Regulations $ 66.8 $ 65.3
US Treasury and Government    
Debt Securities, Available-for-Sale [Line Items]    
Securities held as collateral, at fair value 24.3  
Short-term investments    
Debt Securities, Available-for-Sale [Line Items]    
Securities held as collateral, at fair value 2.2  
Cash and Cash Equivalents and Other Assets    
Debt Securities, Available-for-Sale [Line Items]    
Securities held as collateral, at fair value 1.5  
U.S. government securities    
Debt Securities, Available-for-Sale [Line Items]    
Securities held as collateral, at fair value $ 66.2