XML 69 R53.htm IDEA: XBRL DOCUMENT v3.20.4
Revenue from Contracts with Customers (Details) - USD ($)
 12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Business Acquisition [Line Items]      
Performance obligation satisfied in previous period $ 6,100,000 $ 0 $ 7,300,000
Change in estimate of transaction price 0 0 0
Loss on contracts 0 0 $ 10,000,000.0
Unbilled revenues for unapproved change orders 15,300,000 33,100,000  
Accounts receivable, unapproved contract claims 0 0  
Accounts receivable, contractually billed amounts on contracts related to unapproved contract claims 87,900,000 89,000,000.0  
Net contract liabilities on uncompleted construction projects 496,796,000 406,552,000  
Change in net contract liabilities 104,600,000    
Change in net contract liabilities on uncompleted construction projects 90,200,000    
Contract asset impairment 0    
Accounts receivable, retainage $ 323,900,000 298,500,000  
Accounts receivable, retainage estimated to be collected in next fiscal year 89.00%    
Accounts payable, retainage $ 59,800,000 $ 64,700,000  
Accounts payable, retainage estimated to be paid in next fiscal year 90.00%    
Remaining performance obligations $ 4,594,620,000    
2020 Acquisitions      
Business Acquisition [Line Items]      
Increase (decrease) in contract assets from acquisitions 200,000    
Increase (decrease) in contract liabilities from acquisitions $ 9,400,000