XML 65 R52.htm IDEA: XBRL DOCUMENT v3.24.2.u1
Long-term Debt - Schedule of Debt (Details) - USD ($)
$ in Millions
 3 Months Ended 6 Months Ended
Jun. 30, 2024
Jun. 30, 2023
Jun. 30, 2024
Jun. 30, 2023
Dec. 31, 2023
Carrying amount          
Debt Instrument [Line Items]          
Less: Unamortized debt issuance costs $ (7.2)   $ (7.2)   $ (8.1)
Total debt 337.3   337.3   334.2
Finance lease obligations 24.5   24.5   22.3
Total debt 337.3   337.3   334.2
Less: Current portion of long-term debt 14.1   14.1   13.5
Long-term debt 323.2   323.2   320.7
Interest expense, net of capitalized interest 10.7 $ 13.3 25.4 $ 31.7  
Interest Paid, Capitalized, Investing Activities 12.6 22.9 24.1 41.9  
Other Noncash Income (Expense) 1.9 1.7      
Noncash interest expense, net     3.2 3.3  
Interest Costs Capitalized (1.7) 0.0 (1.7) 0.0  
Financial assurance instruments          
Debt Instrument [Line Items]          
Interest expense, net of capitalized interest 6.1 8.0 14.9 20.0  
Indebtedness          
Debt Instrument [Line Items]          
Interest expense, net of capitalized interest 2.6 2.6 5.2 5.2  
Capital Lease Obligations          
Debt Instrument [Line Items]          
Interest expense, net of capitalized interest 0.5 0.4 0.9 0.9  
Amortization of debt issuance costs          
Debt Instrument [Line Items]          
Interest expense, net of capitalized interest 2.0 0.7 3.2 2.3  
Other          
Debt Instrument [Line Items]          
Interest expense, net of capitalized interest 1.2 $ 1.6 2.9 $ 3.3  
Senior Notes | 3.250% Convertible Senior Notes due March 2028 (2028 Convertible Notes)          
Debt Instrument [Line Items]          
Long-term debt $ 320.0   $ 320.0   $ 320.0
Stated interest rate 3.25%   3.25%