v3.26.1
Long-term Debt - Schedule of Debt (Details) - USD ($)
$ in Millions
 3 Months Ended 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Jun. 02, 2026
Dec. 31, 2025
Carrying amount            
Debt Instrument [Line Items]            
Less: Unamortized debt issuance costs $ (7.5)   $ (7.5)     $ (4.4)
Total debt 339.0   339.0     336.4
Finance lease obligations 17.7   17.7     20.8
Total debt 339.0   339.0     336.4
Less: Current portion of long-term debt 13.5   13.5     15.2
Long-term debt 325.5   325.5     321.2
Interest Expense, Operating and Nonoperating 12.7 $ 11.1 23.4 $ 22.6    
Cash paid for interest, net of capitalized interest 23.4 14.2 33.3 24.1    
Noncash interest expense, net 1.4 1.7 2.8 3.3    
Capitalized interest 0.0 (1.7) (2.1) (3.9)    
3.250% Convertible Senior Notes due March 2028 (2028 Convertible Notes)            
Debt Instrument [Line Items]            
Interest Expense, Operating and Nonoperating 2.0 2.6 4.6 5.2    
Finance lease obligations            
Debt Instrument [Line Items]            
Interest Expense, Operating and Nonoperating 0.4 0.3 0.7 0.7    
Financial assurance instruments            
Debt Instrument [Line Items]            
Interest Expense, Operating and Nonoperating 6.2 6.4 12.9 13.6    
Amortization of debt issuance costs            
Debt Instrument [Line Items]            
Interest Expense, Operating and Nonoperating 1.4 1.4 2.8 2.8    
Accounts Receivable Securitization Program            
Debt Instrument [Line Items]            
Interest Expense, Operating and Nonoperating 0.6 0.6 1.2 1.2    
Other            
Debt Instrument [Line Items]            
Interest Expense, Operating and Nonoperating 2.0 1.5 3.2 3.0    
0.500% Convertible Notes due June 2031            
Debt Instrument [Line Items]            
Interest Expense, Operating and Nonoperating 0.1 0.0 0.1 0.0    
Senior Notes | 3.250% Convertible Senior Notes due March 2028 (2028 Convertible Notes)            
Debt Instrument [Line Items]            
2028 Convertible Notes $ 78.8   $ 78.8     320.0
Less: Unamortized debt issuance costs         $ (2.7)  
Stated interest rate 3.25%   3.25%      
Senior Notes | 0.500% Convertible Notes due June 2031            
Debt Instrument [Line Items]            
Stated interest rate 0.50%   0.50%      
Senior Notes | 0.50% Convertible Senior Notes due June 2031 (2031 Convertible Notes)            
Debt Instrument [Line Items]            
2028 Convertible Notes $ 250.0   $ 250.0     $ 0.0
Secured debt | Accounts Receivable Securitization Program            
Debt Instrument [Line Items]            
Interest Expense, Operating and Nonoperating   $ 0.6   $ 1.2