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Significant Accounting Policies - Additional Information (Detail)
$ in Millions
9 Months Ended
Sep. 30, 2020
USD ($)
Facility
State
Segment
Oct. 29, 2020
USD ($)
Significant Accounting Policies [Line Items]    
Number of quarries and yards | Facility 290  
Number of states with aggregates business sales by destination | State 27  
Reportable business segments | Segment 2  
Restricted cash $ 77.1  
Number of days restricted from utilizing cash 180 days  
Subsequent Event    
Significant Accounting Policies [Line Items]    
Restricted cash   $ 45.1