XML 71 R53.htm IDEA: XBRL DOCUMENT v3.24.0.1
Income Taxes - Tax Effects of Significant Temporary Differences Creating Deferred Tax Assets and Liabilities (Details) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2023
Dec. 31, 2022
Dec. 31, 2021
Deferred Tax Assets, Gross [Abstract]      
Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Employee Benefits $ 3.6 $ 3.2  
Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Postretirement Benefits 13.1 12.9  
Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Employee Compensation 3.7 3.5  
Deferred Tax Assets, Inventory 1.2 2.2  
Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Pensions 0.0 0.9  
Deferred Tax Assets, Tax Credit Carryforwards 10.6 10.1  
Deferred Tax Assets, Operating Loss Carryforwards 1.3 3.3  
Deferred Tax Assets, in Process Research and Development 8.0 2.7  
Deferred tax assets, gross 57.5 50.8  
Deferred Tax Assets, Valuation Allowance 9.0 10.8  
Deferred Tax Assets, Net of Valuation Allowance 48.4 40.0  
Tax position taken in current year 0.4 68.6 $ 0.2
Unrecognized Tax Benefits, Increase Resulting from Prior Period Tax Positions 10.4 0.1 $ 0.7
Deferred tax liabilities:      
Plant and equipment (158.3) (168.3)  
Deferred Tax Liabilities, Leasing Arrangements (15.0) (10.8)  
Deferred Tax Liabilities, Tax Deferred Expense, Compensation and Benefits Pension and Other Postretirement Benefits (0.5) 0.0  
Intangible assets (1.3) (1.8)  
Deferred Tax Liabilities, Other (1.4) (1.2)  
Deferred Tax Liabilities, Gross 176.5 182.1  
Deferred Tax Liabilities, Net 128.1 142.1  
Lease Agreements [Member]      
Deferred Tax Assets, Gross [Abstract]      
Deferred Tax Assets, Other $ 16.0 $ 12.0