Document and Entity Information - USD ($) $ in Billions	12 Months Ended
	Dec. 31, 2014	Jul. 27, 2015	Jun. 30, 2014
Document and Entity Information [Abstract]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Dec. 31, 2014
Document Fiscal Year Focus	2014
Document Fiscal Period Focus	FY
Entity Registrant Name	MASTEC INC
Trading Symbol	MTZ
Entity Central Index Key	0000015615
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	No
Entity Filer Category	Large Accelerated Filer
Entity Public Float (in dollars)			$ 2.0
Entity Common Stock, Shares Outstanding		79,839,747