v3.26.1
Financial Instruments - Financial Instruments not Carried at Fair Value but which Require Fair Value Disclosure (Detail) - USD ($)
$ in Millions
Jun. 30, 2026
Dec. 31, 2025
Carrying amount    
Financial instruments    
Cash, cash equivalents and restricted cash $ 34.5 $ 42.5
Revolving credit facility 28.2  
Fair value    
Financial instruments    
Cash, cash equivalents and restricted cash 34.5 $ 42.5
Revolving credit facility $ 28.2  
9.50% Senior Secured Notes due 2029    
Financial instruments    
Debt instrument interest rate 9.50% 9.50%
9.50% Senior Secured Notes due 2029 | Carrying amount    
Financial instruments    
Long-term debt - Fixed rate $ 487.7 $ 503.7
9.50% Senior Secured Notes due 2029 | Fair value    
Financial instruments    
Long-term debt - Fixed rate $ 478.8 $ 469.9