Earnings Per Share (Schedule of Earnings Per Share Information) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Net income attributable to MasTec:
Net income - basic (in dollars)	$ 116,491	$ 128,596	$ 209,726	$ 291,418
Net income - diluted (in dollars)	$ 116,491	$ 128,596	$ 209,726	$ 291,418
Weighted average shares outstanding:
Weighted average shares outstanding - basic	72,138,000	75,217,000	72,971,000	75,131,000
Dilutive common stock equivalents (in shares)	957,000	717,000	816,000	629,000
Weighted average shares outstanding - diluted	73,095,000	75,934,000	73,787,000	75,760,000
Anti-dilutive common stock (in shares)			58,759