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Commitments and Contingencies - Environmental (Details)
$ in Millions
1 Months Ended 12 Months Ended 36 Months Ended
Feb. 28, 2022
USD ($)
MMcf
Jan. 31, 2018
USD ($)
unilateral_administrative_order
Sep. 30, 2014
USD ($)
property
Dec. 25, 2021
USD ($)
Dec. 26, 2020
USD ($)
Dec. 28, 2019
USD ($)
Dec. 25, 2021
USD ($)
Dec. 28, 2019
USD ($)
Dec. 25, 2021
smelter_site
Dec. 25, 2021
potentially_responsible_party
Site Contingency [Line Items]                    
Environmental expense       $ 5.0 $ 4.2 $ 1.7        
Environmental reserves       27.4 $ 24.0   $ 27.4      
Expected environmental expenditures for 2022       9.6     9.6      
Expected environmental expenditures for 2023       3.1     3.1      
Expected environmental expenditures for 2024       0.8     0.8      
Expected environmental expenditures for 2025       0.9     0.9      
Expected environmental expenditures for 2026       0.7     0.7      
Expected environmental expenditures after 2026       $ 12.3     12.3      
East La Harpe                    
Site Contingency [Line Items]                    
Number of parties involved in settlement negotiations                 3 2
Southeast Kansas Sites | Subsequent Event                    
Site Contingency [Line Items]                    
Environmental reserves $ 5.6                  
Geographic boundary of sites | MMcf 50                  
Shasta Area Mine Sites                    
Site Contingency [Line Items]                    
Period of permit, implementation of Best Management Practices       10 years            
Environmental remediation expense spending               $ 1.5    
Estimated number of years until mitigation resolution       30 years            
Shasta Area Mine Sites | Minimum                    
Site Contingency [Line Items]                    
Mitigation estimates       $ 14.0            
Shasta Area Mine Sites | Maximum                    
Site Contingency [Line Items]                    
Mitigation estimates       16.0            
Lead Refinery Site                    
Site Contingency [Line Items]                    
Environmental expense             0.5      
Lead Refinery Site [Abstract]                    
EPA's estimated cost of site remediation     $ 26.0              
Number of surrounding properties | property     300              
Site contingency, financial guarantee       $ 1.0     1.0      
Lead Refinery Site | Non operating Properties                    
Site Contingency [Line Items]                    
Estimated number of years until mitigation resolution       15 years            
Lead Refinery Site | Minimum                    
Site Contingency [Line Items]                    
Mitigation estimates       $ 1.6            
Lead Refinery Site | Maximum                    
Site Contingency [Line Items]                    
Mitigation estimates       2.3            
Lead Refinery NPL Site                    
Site Contingency [Line Items]                    
Environmental reserves   $ 4.5                
Lead Refinery Site [Abstract]                    
Number of UAOs issued | unilateral_administrative_order   2                
Site contingency, total costs   $ 25.0                
Site contingency, amount agreed upon to pay PRPs for past costs   2.0                
Possible further payments for ongoing work by PRPs   $ 0.7                
Payments for unilateral administrative orders       7.6            
Loss contingency accrual       3.3     $ 3.3      
Mueller Copper Tube Products, Inc. | Minimum                    
Site Contingency [Line Items]                    
Mitigation estimates       0.7            
Mueller Copper Tube Products, Inc. | Maximum                    
Site Contingency [Line Items]                    
Mitigation estimates       $ 0.9