Annual report pursuant to Section 13 and 15(d)

Document and Entity Information

v3.3.1.900
Document and Entity Information - USD ($)
$ in Billions
12 Months Ended
Dec. 31, 2015
Feb. 23, 2016
Jun. 30, 2015
Document Information [Line Items]      
Document Type 10-K    
Amendment Flag false    
Document Period End Date Dec. 31, 2015    
Document Fiscal Year Focus 2015    
Document Fiscal Period Focus FY    
Trading Symbol PWR    
Entity Registrant Name QUANTA SERVICES INC    
Entity Central Index Key 0001050915    
Current Fiscal Year End Date --12-31    
Entity Well-known Seasoned Issuer Yes    
Entity Current Reporting Status Yes    
Entity Voluntary Filers No    
Entity Filer Category Large Accelerated Filer    
Entity Common Stock, Shares Outstanding   152,907,166  
Entity Public Float     $ 5.7
Series F Preferred Stock [Member]      
Document Information [Line Items]      
Entity Common Stock, Shares Outstanding   1  
Series G Preferred Stock [Member]      
Document Information [Line Items]      
Entity Common Stock, Shares Outstanding   1  
Exchangeable Shares Associated with Series F Preferred Stock [Member]      
Document Information [Line Items]      
Entity Common Stock, Shares Outstanding   3,500,000  
Exchangeable Shares Associated with Series G Preferred Stock [Member]      
Document Information [Line Items]      
Entity Common Stock, Shares Outstanding   449,929  
Exchangeable Shares Not Associated with Preferred Stock [Member]      
Document Information [Line Items]      
Entity Common Stock, Shares Outstanding   2,926,113