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Goodwill and Other Intangible Assets - Summary of Goodwill By Segments (Details) - USD ($)
$ in Thousands
Dec. 31, 2020
Dec. 31, 2019
Goodwill [Line Items]    
Goodwill $ 192,014 $ 191,892
Heavy Civil Construction    
Goodwill [Line Items]    
Goodwill 54,806 54,806
Specialty Service    
Goodwill [Line Items]    
Goodwill 106,783 106,661
Residential    
Goodwill [Line Items]    
Goodwill $ 30,425 $ 30,425