Earnings Per Share (Schedule Of Earnings Per Share Information) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended				9 Months Ended
	Sep. 30, 2014		Sep. 30, 2013		Sep. 30, 2014		Sep. 30, 2013
Net income attributable to MasTec:
Net income, continuing operations - basic	$ 45,591	[1]	$ 49,960	[1]	$ 93,936	[1]	$ 104,702	[1]
Net income attributable to MasTec - diluted	45,291		46,217		93,510		99,685
Net loss from discontinued operations - basic and diluted	(320)	[1]	(3,822)	[1]	(592)	[1]	(5,253)	[1]
Weighted average shares outstanding:
Weighted average shares outstanding - basic	81,811		77,093		79,158		76,816
Dilutive common stock equivalents	814		775		798		774
Weighted average shares outstanding - diluted	85,824		85,464		86,416		84,733
Continuing Operations [Member]
Net income attributable to MasTec:
Net income attributable to MasTec - diluted	45,611		50,039		94,102		104,938
2009 Convertible Notes [Member]
Net income attributable to MasTec:
Interest expense, net of tax, 2009 Convertible Notes	$ 20		$ 79		$ 166		$ 236
Weighted average shares outstanding:
Dilutive shares, 2009 Convertible Notes	194		806		560		806
2011 Convertible Notes [Member] | Convertible Debt [Member]
Weighted average shares outstanding:
Dilutive premium shares, 2011 Convertible Notes	3,005		6,790		5,900		6,337

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