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Benefit Plans - Company's Participation in Multiemployer Plans Individually Significant (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Multiemployer Plans [Line Items]      
Contributions $ 5.7    
Employer contribution percentage, greater than 5% 5.00%    
Surcharge percentage during first twelve months 5.00%    
Surcharge percentage after 12 months 10.00%    
Suburban Teamsters of Northern IL Pension Fund      
Multiemployer Plans [Line Items]      
Contributions $ 0.7 $ 0.6 $ 0.6
Pension Fund of Automobile Mechanics Local No. 701      
Multiemployer Plans [Line Items]      
Contributions 0.2 0.2 0.2
Local 731 Private Scavengers and Garage Attendants Pension Fund      
Multiemployer Plans [Line Items]      
Contributions 1.9 1.8 1.8
Midwest Operating Engineers Pension Fund      
Multiemployer Plans [Line Items]      
Contributions 1.0 0.9 0.7
Teamsters Local Union No. 301 Union Pension Fund (A)      
Multiemployer Plans [Line Items]      
Contributions 1.3 1.1 1.0
Central States Southeast and Southwest Areas Pension Fund      
Multiemployer Plans [Line Items]      
Contributions 0.2 0.2 0.2
Local 705 Int’l Brotherhood of Teamsters Pension TR. FD.      
Multiemployer Plans [Line Items]      
Contributions $ 0.2 $ 0.2 $ 0.2