Quarterly Information (Unaudited) (Schedule of Quarterly Financial Information (Unaudited)) (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017		Dec. 31, 2016		Dec. 31, 2015
Selected Quarterly Financial Information [Abstract]
Revenue	$ 1,602,900	$ 1,955,800	$ 1,890,200	$ 1,158,200	$ 1,341,900	$ 1,586,200	$ 1,232,400	$ 974,200	$ 6,606,978		$ 5,134,703		$ 4,208,330
Costs of revenue, excluding depreciation and amortization	1,421,700	1,726,200	1,626,300	971,100	1,120,600	1,369,000	1,068,200	884,400	5,745,307		4,442,125		3,721,303
Net income (loss)	160,700	64,200	83,300	40,600	55,900	56,500	24,400	(2,900)	348,884		134,035		(79,703)
Net income (loss) attributable to MasTec, Inc.	$ 160,800	$ 63,800	$ 81,700	$ 41,000	$ 53,600	$ 56,300	$ 24,100	$ (2,700)	$ 347,213	[1]	$ 131,263	[1]	$ (79,110)	[1]
Earnings (loss) per share:
Basic (in dollars per share)	$ 1.98	$ 0.79	$ 1.01	$ 0.51	$ 0.67	$ 0.70	$ 0.30	$ (0.03)	$ 4.29		$ 1.63		$ (0.98)
Diluted (in dollars per share)	$ 1.95	$ 0.77	$ 0.99	$ 0.50	$ 0.66	$ 0.69	$ 0.30	$ (0.03)	$ 4.22		$ 1.61		$ (0.98)

[1] Calculated as total net income (loss) less amounts attributable to non-controlling interests.