Quarterly report pursuant to Section 13 or 15(d)

Acquisitions (Detail)

v3.7.0.1
Acquisitions (Detail)
$ in Thousands
 3 Months Ended 6 Months Ended 12 Months Ended
Jun. 30, 2017
USD ($)
shares
Jun. 30, 2016
USD ($)
Jun. 30, 2017
USD ($)
Jun. 30, 2016
USD ($)
Jun. 30, 2017
USD ($)
Dec. 31, 2016
USD ($)
Acquisition
shares
Business Acquisition [Line Items]            
Net tangible assets acquired         $ 22,900  
Goodwill acquired     $ 1,484   19,200  
Other intangible assets acquired         10,200  
Revenues included in consolidated results of operations $ 2,200,374 $ 1,792,430 4,378,544 $ 3,506,167    
Loss (income) before taxes (104,605) $ (31,424) (175,637) $ (65,726)    
Electric Power Infrastructure Services Division            
Business Acquisition [Line Items]            
Goodwill acquired     1,484      
Oil and Gas Infrastructure Services Division            
Business Acquisition [Line Items]            
Goodwill acquired     0      
Acquisitions 2017            
Business Acquisition [Line Items]            
Cash paid or payable $ 5,600   5,554      
Number of shares granted for acquired companies (in shares) | shares 288,666          
Value of Quanta common stock issued $ 8,300   8,267      
Contingent consideration, liability 0   0   0  
Goodwill acquired     1,484      
Fair value of accounts receivable acquired 6,300   6,300   6,300  
Goodwill expected to be deductible for income tax 1,500   1,500   $ 1,500  
Revenues included in consolidated results of operations 2,200   2,200      
Loss (income) before taxes 1,800   1,800      
Acquisition costs $ 2,300   2,300      
Acquisitions 2017 | Electric Power Infrastructure Services Division            
Business Acquisition [Line Items]            
Goodwill acquired     $ 1,500      
Acquisitions 2016            
Business Acquisition [Line Items]            
Cash paid or payable           $ 75,941
Number of shares granted for acquired companies (in shares) | shares           70,840
Value of Quanta common stock issued           $ 1,508
Number of business acquisitions | Acquisition           5
Contingent consideration, maximum           $ 39,500
Contingent consideration, liability           18,683
Goodwill acquired           43,923
Fair value of accounts receivable acquired           14,400
Goodwill expected to be deductible for income tax           $ 2,000
Acquisitions 2016 | Electric Power Infrastructure Services Segment            
Business Acquisition [Line Items]            
Number of business acquisitions | Acquisition           4
Acquisitions 2016 | Electric Power Infrastructure Services Division            
Business Acquisition [Line Items]            
Goodwill acquired           $ 23,600
Acquisitions 2016 | Oil and Gas Infrastructure Services Division            
Business Acquisition [Line Items]            
Goodwill acquired           $ 20,300