Acquisitions (Schedule of Business Acquisition Pro Forma Information) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
2013 Acquisitions [Member]
Business Acquisition [Line Items]
Pro forma information, description			The unaudited pro forma combined results of operations presented below for three and nine month periods ended September 30, 2013 and 2012, respectively, have been prepared by adjusting the historical results of MasTec to include the historical results of the acquisitions described above as if they occurred on January 1, 2012. The unaudited pro forma combined historical results were then adjusted (i) to remove one-time acquisition costs; (ii) to increase amortization expense resulting from incremental intangible assets acquired in such acquisitions; (iii) to increase interest expense as a result of the cash consideration paid; and (iv) to reduce interest expense from the repayment of acquired debt. The unaudited pro forma results of operations do not include any adjustments to reflect the impact of cost savings or other synergies that may result from these acquisitions. As noted above, the unaudited pro forma results of operations do not purport to be indicative of the actual results that would have been achieved by the combined companies for the periods presented or that may be achieved by the combined company in the future.
Pro forma revenue	$ 1,273.6	$ 1,158.7	$ 3,284.9	$ 3,026.2
Pro forma net income from continuing operations	50.0	42.7	113.4	88.9
Aquiree revenue since acquisition date	101.8		141.4
Acquiree net income since acquisition date	6.2		7.7
2012 Acquisitions [Member]
Business Acquisition [Line Items]
Aquiree revenue since acquisition date	39.9		129.0
Acquiree net income since acquisition date	$ 1.4		$ 5.2