Consolidated Statements of Operations - USD ($) shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018		Dec. 31, 2017		Dec. 31, 2016
Income Statement [Abstract]
Revenue	$ 1,917,600	$ 1,977,200	$ 1,617,800	$ 1,396,800	$ 1,602,900	$ 1,955,800	$ 1,890,200	$ 1,158,200	$ 6,909,417		$ 6,606,978		$ 5,134,703
Costs of revenue, excluding depreciation and amortization	1,654,000	1,681,400	1,366,600	1,237,300	1,421,700	1,726,200	1,626,300	971,100	5,939,308		5,745,307		4,442,125
Depreciation and amortization									212,930		188,049		164,915
Goodwill impairment	47,700								47,662		0		0
General and administrative expenses									287,278		275,103		261,433
Interest expense, net									82,571		61,011		50,734
Equity in earnings of unconsolidated affiliates									(23,855)		(21,328)		(3,528)
Other income, net									(1,780)		(12,990)		(6,795)
Income before income taxes									365,303		371,826		225,819
Provision for income taxes									(106,072)		(22,942)		(91,784)
Net income	31,800	120,500	80,400	26,500	160,700	64,200	83,300	40,600	259,231		348,884		134,035
Net (loss) income attributable to non-controlling interests									(428)		1,671		2,772
Net income attributable to MasTec, Inc.	$ 31,900	$ 120,700	$ 80,500	$ 26,600	$ 160,800	$ 63,800	$ 81,700	$ 41,000	$ 259,659	[1]	$ 347,213	[1]	$ 131,263	[1]
Earnings per share (Note 2):
Basic earnings per share (in dollars per share)	$ 0.42	$ 1.55	$ 1.02	$ 0.33	$ 1.98	$ 0.79	$ 1.01	$ 0.51	$ 3.30		$ 4.29		$ 1.63
Basic weighted average common shares outstanding									78,695		80,903		80,372
Diluted earnings per share (in dollars per share)	$ 0.41	$ 1.52	$ 1.01	$ 0.32	$ 1.95	$ 0.77	$ 0.99	$ 0.50	$ 3.26		$ 4.22		$ 1.61
Diluted weighted average common shares outstanding									79,772		82,325		81,394

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