Acquisitions - 2011 Acquisitions (Narrative) (Details) (USD $)	12 Months Ended						0 Months Ended	3 Months Ended	12 Months Ended					0 Months Ended	12 Months Ended	32 Months Ended		0 Months Ended	12 Months Ended		12 Months Ended		0 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2013 Earn-out Arrangements [Member]	Dec. 31, 2012 Earn-out Arrangements [Member]	Dec. 31, 2011 Earn-out Arrangements [Member]	May 02, 2011 EC Source [Member]	Jun. 30, 2011 EC Source [Member]	Dec. 31, 2013 EC Source [Member]	May 03, 2011 EC Source [Member]	May 03, 2011 EC Source [Member] Pre-Qualifications [Member]	Dec. 31, 2013 EC Source [Member] Investor [Member]	May 03, 2011 EC Source [Member] Investor [Member]	May 02, 2011 EC Source [Member] Earn-out Arrangements [Member]	Dec. 31, 2013 EC Source [Member] Earn-out Arrangements [Member]	Dec. 31, 2013 EC Source [Member] Earn-out Arrangements [Member]	May 03, 2011 EC Source [Member] Earn-out Arrangements [Member]	May 02, 2011 EC Source [Member] Common Stock [Member]	Dec. 31, 2013 EC Source [Member] Common Stock [Member]	May 03, 2011 EC Source [Member] Common Stock [Member]	Dec. 31, 2013 Other 2011 Acquisitions [Member]	Nov. 30, 2010 E C Source Services Llc Investee [Member]	May 02, 2011 Backlog [Member] EC Source [Member]	May 02, 2011 Non-compete Agreements [Member] EC Source [Member]
Business Acquisition [Line Items]
Investment, ownership percentage																						33.00%
Business acquisition, name of acquired entity									EC Source Services LLC
Business acquisition, description of acquired entity									a nationally recognized full-service engineering, procurement and construction services company that installs extra high voltage (“EHV”) electrical transmission systems throughout North America												Effective April 1, 2011, MasTec acquired a company based in western Canada that provides natural gas and petroleum pipeline infrastructure construction services, which is included in the Company's Oil and Gas segment. MasTec also purchased a company that provides telephone, cabling, engineering, construction, equipment integration, testing, wiring and computer network services to telecommunications carriers effective April 1, 2011, which is included in the Company's Communications segment. In addition, effective June 1, 2011, MasTec acquired a self-perform wireless infrastructure services company headquartered in California, which is included in the Company's communications segment. Effective June 30, 2011, MasTec also acquired an install-to-the-home contractor, which is included in the Company's Communications segment, that operates primarily in portions of New York, Pennsylvania and New England, and whose primary customer is DIRECTV®.
Effective date of acquisition									May 02, 2011
Business combination, percentage of voting interests acquired										67.00%
Business combination, step acquisition, cumulative percentage ownership after all transactions							100.00%
Equity issued in business combination, number of shares issued																		5,129,642
Equity issued in business combination, fair value																				$ 94,200,000
Acquisition payments in cash							300,000
Earn-out period																	5 years
Estimated fair value of contingent consideration				29,971,000	66,700,000	48,111,000								25,000,000
Business combination, contingent consideration arrangements, basis for amount															The earn-out is equal to 20% of the excess, if any, of EC Source’s EBITDA, as defined in the purchase agreement, over $15 million, payable annually at MasTec’s election in common stock, cash or a combination thereof.
Business combination, equity interest issued or issuable, description																			The MasTec shares issued on the effective date are subject to transfer restrictions, 25% of which lapsed on May 2, 2012, 25% of which lapsed on May 2, 2013, and 50% of which will lapse on May 2, 2014.
Business combination, assumed debt	9,800,000	20,600,000										2,600,000	8,600,000
Business combination, cost of acquired entity, equity interests issued and issuable, fair value method																			The fair value of the shares transferred was based on MasTec’s quoted market price on the closing date, discounted by 10%, 15% and 20% for the estimated effect of the first, second and third year transfer restrictions, respectively.
Business combination, step acquisition, equity interest in acquiree, percentage										33.00%
Business combination, step acquisition, equity interest in acquiree, fair value of equity investment							39,600,000
Gain on remeasurement of equity interest in acquiree	0	0	29,041,000					29,000,000
Business combination, step acquisition, equity interest in acquiree, valuation techniques									The fair value of the equity investment was determined based on the implied consideration transferred as of the date of the business combination, discounted for the Company’s lack of control as a minority shareholder.
Finite-lived intangible assets										12,500,000
Non-amortizing intangible assets											31,300,000
Finite-lived intangible asset, useful life																							3 years	7 years
Business combination, goodwill recognized, description									Goodwill arising from the acquisition represents the estimated value of EC Source's geographic presence in key high growth markets, its assembled workforce, its management team's industry-specific project management expertise and synergies expected to be achieved from the combined operations of EC Source and MasTec.
Business combination, goodwill, expected tax deductible amount										0
Fair value measurements, significant assumptions															The fair value of the earn-out obligation was estimated using an income approach and incorporates significant inputs not observable in the market. Key assumptions in the estimated valuation include the discount rate and probability-adjusted EBITDA projections.
Business combination, contingent consideration arrangements, range of outcomes, value, low																	0
Business combination, contingent consideration arrangements, range of outcomes, value, high																	55,000,000
Business combination, contingent consideration arrangements, range of outcomes, maximum unlimited															there is no maximum earn-out payment amount.
Business combination, contingent consideration arrangements, earn-out payments				18,683,000	33,936,000	44,714,000										7,800,000
Business combination, contingent consideration, liability															$ 19,500,000	$ 19,500,000