v3.26.1
FINANCIAL INSTRUMENTS AND FAIR VALUE - Schedule of Investments at Fair Value (Details) - Recurring - USD ($)
$ in Millions
Jun. 30, 2026
Dec. 31, 2025
Total    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Cash equivalents $ 3.3 $ 6.7
Investments, fair value 421.8 415.3
Total | Short-term investments    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments, fair value 5.3 0.5
Total | Municipal    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments, fair value 4.9 5.0
Total | Mortgage and other asset-backed securities    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments, fair value 246.1 240.1
Total | Corporate    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments, fair value 162.7 167.0
Total | U.S. Treasuries    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments, fair value 2.7 2.6
Level 1    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Cash equivalents 3.3 6.7
Investments, fair value 3.9 3.5
Level 1 | Short-term investments    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments, fair value 0.8 0.5
Level 1 | Municipal    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments, fair value 0.0 0.0
Level 1 | Mortgage and other asset-backed securities    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments, fair value 0.0 0.0
Level 1 | Corporate    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments, fair value 0.3 0.3
Level 1 | U.S. Treasuries    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments, fair value 2.7 2.6
Level 2    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Cash equivalents 0.0 0.0
Investments, fair value 417.9 411.8
Level 2 | Short-term investments    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments, fair value 4.5 0.0
Level 2 | Municipal    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments, fair value 4.9 5.0
Level 2 | Mortgage and other asset-backed securities    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments, fair value 246.1 240.1
Level 2 | Corporate    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments, fair value 162.4 166.7
Level 2 | U.S. Treasuries    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments, fair value 0.0 0.0
Level 3    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Cash equivalents 0.0 0.0
Investments, fair value 0.0 0.0
Level 3 | Short-term investments    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments, fair value 0.0 0.0
Level 3 | Municipal    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments, fair value 0.0 0.0
Level 3 | Mortgage and other asset-backed securities    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments, fair value 0.0 0.0
Level 3 | Corporate    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments, fair value 0.0 0.0
Level 3 | U.S. Treasuries    
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]    
Investments, fair value $ 0.0 $ 0.0