Consolidated Statements of Operations - USD ($) shares in Thousands, $ 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
Income Statement [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
Depreciation and amortization									188,049		164,915		169,662
Goodwill and intangible asset impairment									0		0		78,625
General and administrative expenses									275,103		261,433		265,910
Interest expense, net									61,011		50,734		48,055
Equity in (earnings) losses of unconsolidated affiliates									(21,328)		(3,528)		7,978
Other income, net									(12,990)		(6,795)		(15,457)
Income (loss) before income taxes									371,826		225,819		(67,746)
Provision for income taxes									(22,942)		(91,784)		(11,957)
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 non-controlling interests									1,671		2,772		(593)
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 (Note 2):
Basic earnings (loss) per share (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)
Basic weighted average common shares outstanding									80,903		80,372		80,489
Diluted earnings (loss) per share (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)
Diluted weighted average common shares outstanding									82,325		81,394		80,489

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