Earnings Per Share (Schedule of Earnings Per Share Information) (Details) - USD ($) shares in Thousands, $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Net income attributable to MasTec:
Net income - basic (in dollars)	[1]	$ 120,666	$ 63,752	$ 227,718	$ 186,390
Net income - diluted (in dollars)	[1]	$ 120,666	$ 63,752	$ 227,718	$ 186,390
Weighted average shares outstanding:
Weighted average shares outstanding - basic		78,096	80,953	79,399	80,859
Dilutive common stock equivalents (in shares)		1,105	1,433	1,085	1,422
Weighted average shares outstanding - diluted		79,201	82,386	80,484	82,281
Common Stock [Member]
Additional information:
Weighted average anti-dilutive common stock equivalents (in shares)	[2]	0	0	0	12

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

[2] Represents anti-dilutive common stock equivalents as calculated under the treasury stock method.