Earnings Per Share (Schedule of Earnings Per Share Information) (Details) - USD ($) shares in Thousands, $ in Thousands		3 Months Ended		9 Months Ended
		Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Net income (loss) attributable to MasTec:
Net income (loss), continuing operations - basic (in dollars)	[1]	$ 7,618	$ 49,306	$ (2,346)	$ 95,399
Interest expense, net of tax, convertible notes (in dollars)		0	20	0	166
Net income (loss) attributable to MasTec - diluted (in dollars)		7,618	49,006	(2,346)	94,973
Net loss from discontinued operations - basic and diluted (in dollars)	[1]	$ 0	$ (320)	$ 0	$ (592)
Weighted average shares outstanding:
Weighted average shares outstanding - basic		79,845	81,811	80,681	79,158
Dilutive common stock equivalents (in shares)		603	814	0	798
Weighted average shares outstanding - diluted		80,448	85,824	80,681	86,416
Convertible Debt [Member]
Weighted average shares outstanding:
Dilutive shares, convertible notes		0	3,199	0	6,460
Continuing Operations [Member]
Net income (loss) attributable to MasTec:
Net income (loss) attributable to MasTec - diluted (in dollars)		$ 7,618	$ 49,326	$ (2,346)	$ 95,565

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