Consolidated Statements of Equity - USD ($) $ in Thousands	Total	Cumulative effect of adoption, revenue recognition (Topic 606)	Common Stock [Member]	Treasury Stock [Member]	Capital Surplus [Member]	Retained Earnings [Member]	Retained Earnings [Member] Cumulative effect of adoption, revenue recognition (Topic 606)	Accumulated Other Comprehensive Loss [Member]	Total MasTec, Inc. Shareholders’ Equity [Member]	Total MasTec, Inc. Shareholders’ Equity [Member] Cumulative effect of adoption, revenue recognition (Topic 606)	Non-Controlling Interests [Member]
Beginning balance, common shares outstanding (in shares) at Dec. 31, 2017			90,935,584
Beginning balance at Dec. 31, 2017	$ 1,433,353	$ 1,562	$ 9,094	$ (147,124)	$ 775,387	$ 857,154	$ 1,562	$ (63,712)	$ 1,430,799	$ 1,562	$ 2,554
Beginning balance, treasury shares (in shares) at Dec. 31, 2017				(8,132,811)
Consolidated Statements of Equity
Net income (loss)	259,231					259,659			259,659		(428)
Other comprehensive income (loss)	3,218							3,218	3,218
Non-cash stock-based compensation	13,527				13,527				13,527
Issuance of restricted shares, net (in shares)			385,392
Issuance of restricted shares, net	0		$ 39		(39)				0
Other stock issuances, net of shares withheld for taxes (in shares)			6,033
Other stock issuances, net of shares withheld for taxes	$ 134		$ 0		134				134
Acquisition of treasury stock, at cost (in shares)	(7,200,000)			(7,197,006)
Acquisition of treasury stock, at cost	$ (319,001)			$ (319,001)					(319,001)
Ending balance, common shares outstanding (in shares) at Dec. 31, 2018			91,327,009
Ending balance at Dec. 31, 2018	$ 1,392,024		$ 9,133	$ (466,125)	789,009	1,118,375		(60,494)	1,389,898		2,126
Ending balance, treasury shares (in shares) at Dec. 31, 2018				(15,329,817)
Consolidated Statements of Equity
Accounting Standards Update [Extensible List]	us-gaap:AccountingStandardsUpdate201409Member
Net income (loss)	$ 394,096					392,334			392,334		1,762
Other comprehensive income (loss)	(15,212)							(15,212)	(15,212)
Non-cash stock-based compensation	16,447				16,447				16,447
Issuance of restricted shares, net (in shares)			464,970
Issuance of restricted shares, net	0		$ 46		(46)				0
Other stock issuances, net of shares withheld for taxes (in shares)			117,451
Other stock issuances, net of shares withheld for taxes	4,355		$ 12		4,343				4,355
Acquisition of treasury stock, at cost (in shares)				(15,100)
Acquisition of treasury stock, at cost	(602)			$ (602)					(602)
Contributions from non-controlling interests	$ 583								0		583
Ending balance, common shares outstanding (in shares) at Dec. 31, 2019	91,909,430		91,909,430
Ending balance at Dec. 31, 2019	$ 1,791,691		$ 9,191	$ (466,727)	809,753	1,510,709		(75,706)	1,787,220		4,471
Ending balance, treasury shares (in shares) at Dec. 31, 2019	(15,344,917)			(15,344,917)
Consolidated Statements of Equity
Net income (loss)	$ 322,699					322,848			322,848		(149)
Other comprehensive income (loss)	(15,738)							(15,738)	(15,738)
Non-cash stock-based compensation	21,875				21,875				21,875
Issuance of restricted shares, net (in shares)			993,893
Issuance of restricted shares, net	0		$ 99		(99)				0
Other stock issuances, net of shares withheld for taxes (in shares)			204,117
Other stock issuances, net of shares withheld for taxes	$ 5,945		$ 21		5,924				5,945
Acquisition of treasury stock, at cost (in shares)	(3,600,000)			(3,597,009)
Acquisition of treasury stock, at cost	$ (120,228)			$ (120,228)					(120,228)
Distributions to non-controlling interests	$ (719)								0		(719)
Ending balance, common shares outstanding (in shares) at Dec. 31, 2020	93,107,440		93,107,440
Ending balance at Dec. 31, 2020	$ 2,005,525		$ 9,311	$ (586,955)	$ 837,453	$ 1,833,557		$ (91,444)	$ 2,001,922		$ 3,603
Ending balance, treasury shares (in shares) at Dec. 31, 2020	(18,941,926)			(18,941,926)