v3.26.1
Long-term debt - Components of Long-Term Debt (Detail) - USD ($)
$ in Millions
Mar. 31, 2026
Dec. 31, 2025
Long-term debt    
Revolving credit facility $ 58.1  
Total debt 602.7 $ 557.4
Total long-term debt 602.7 557.4
Subordinated, Unsecured Term Loan from Contran    
Long-term debt    
Subordinated debt 53.7 53.7
Kronos International, Inc | 9.50% Senior Secured Notes due 2029    
Long-term debt    
Kronos International, Inc. $ 490.9 $ 503.7