Cover Page - shares	6 Months Ended
	Jun. 30, 2023	Jul. 28, 2023
Document And Entity Information [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Jun. 30, 2023
Document Transition Report	false
Entity File Number	001-13831
Entity Registrant Name	Quanta Services, Inc.
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	74-2851603
Entity Address, Address Line One	2727 North Loop West
Entity Address, City or Town	Houston
Entity Address, State or Province	TX
Entity Address, Postal Zip Code	77008
City Area Code	713
Local Phone Number	629-7600
Title of 12(b) Security	Common Stock, $0.00001 par value
Trading Symbol	PWR
Security Exchange Name	NYSE
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		145,198,975
Document Fiscal Period Focus	Q2
Amendment Flag	false
Document Fiscal Year Focus	2023
Current Fiscal Year End Date	--12-31
Entity Central Index Key	0001050915