Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Statement of Comprehensive Income [Abstract]
Net income	$ 322,699	$ 394,096	$ 259,231
Other comprehensive (loss) income:
Foreign currency translation gains (losses), net of tax	1,413	(189)	(2,645)
Unrealized (losses) gains on investment activity, net of tax	(17,151)	(15,023)	5,863
Comprehensive income	306,961	378,884	262,449
Comprehensive (loss) income attributable to non-controlling interests	(149)	1,762	(428)
Comprehensive income attributable to MasTec, Inc.	$ 307,110	$ 377,122	$ 262,877