Cover Page - USD ($) $ in Billions	12 Months Ended
	Dec. 31, 2021	Feb. 24, 2022	Jun. 30, 2021
Cover [Abstract]
Document Type	10-K
Document Annual Report	true
Document Period End Date	Dec. 31, 2021
Current Fiscal Year End Date	--12-31
Document Transition Report	false
Entity File Number	001-08106
Entity Registrant Name	MasTec, Inc.
Entity Incorporation, State or Country Code	FL
Entity Tax Identification Number	65-0829355
Entity Address, Address Line One	800 S. Douglas Road, 12th Floor
Entity Address, City or Town	Coral Gables,
Entity Address, State or Province	FL
Entity Address, Postal Zip Code	33134
City Area Code	305
Local Phone Number	599-1800
Title of 12(b) Security	Common Stock, $0.10 Par Value
Trading Symbol	MTZ
Security Exchange Name	NYSE
Entity Well-known Seasoned Issuer	Yes
Entity Voluntary Filers	No
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
ICFR Auditor Attestation Flag	true
Entity Shell Company	false
Entity Public Float (in dollars)			$ 5.9
Entity Common Stock, Shares Outstanding		76,428,997
Documents Incorporated by Reference	The registrant’s definitive proxy statement to be filed with the Securities and Exchange Commission pursuant to Regulation 14A for the 2022 annual meeting of shareholders is incorporated by reference in Part III of this Form 10-K to the extent stated herein.
Entity Central Index Key	0000015615
Document Fiscal Year Focus	2021
Document Fiscal Period Focus	FY
Amendment Flag	false