Segments and Operations by Geographic Area (Narrative) (Details)	3 Months Ended		6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Segment Reporting Information [Line Items]
Number of reportable segments			5
Segment reporting, factors used to identify entity's reportable segments			MasTec presents its continuing operations under five reportable segments: (1) Communications; (2) Oil and Gas; (3) Electrical Transmission; (4) Power Generation and Industrial and (5) Other. This structure is generally focused on broad end-user markets for MasTec's labor-based construction services and has been determined in accordance with the criteria in Accounting Standards Codification ("ASC") 280, Segment Reporting.
Segment reporting information, description of products and services			All five reportable segments derive their revenues from the engineering, installation and maintenance of infrastructure, primarily in North America.
Segment reporting, description of all other segments			The Other category primarily includes small business units that perform construction services for a variety of end markets in Mexico and elsewhere internationally.
Segment reporting, measurement for transactions between reportable segments			Intersegment revenues and costs are accounted for as if the revenues were to third parties because these items are based on negotiated fees between the segments involved. All intercompany transactions and balances are eliminated in consolidation; eliminations between segments are included in the Eliminations reconciling column in the tables below.
Communications [Member]
Segment Reporting Information [Line Items]
Segment reporting information, description of products and services			The Communications segment performs engineering, construction and maintenance of communications infrastructure primarily related to wireless and wireline communications and install-to-the-home, and to a lesser extent, infrastructure for electrical utilities.
Oil and Gas [Member]
Segment Reporting Information [Line Items]
Segment reporting information, description of products and services			MasTec also performs engineering, construction and maintenance services on oil and natural gas pipelines and processing facilities for the energy and utilities industries through the Oil and Gas segment.
Electrical Transmission [Member]
Segment Reporting Information [Line Items]
Segment reporting information, description of products and services			The Electrical Transmission segment primarily serves the energy and utility industries through the engineering, construction and maintenance of electrical transmission lines and substations.
Power Generation and Industrial [Member]
Segment Reporting Information [Line Items]
Segment reporting information, description of products and services			The Power Generation and Industrial segment primarily serves the energy and utility end markets and other end markets through the installation and construction of power plants, wind farms, solar farms, related electrical transmission infrastructure, ethanol facilities and various types of industrial infrastructure.
Segment, Continuing Operations [Member] | Communications [Member] | Sales Revenue, Services, Net [Member] | Utilities [Member] | Reportable Segment [Member]
Segment Reporting Information [Line Items]
Entity-wide revenue by customer type, percentage	6.50%	10.40%	7.30%	11.00%