Independent Investigation of the Audit Committee and Related Restatements (Restated Condensed Unaudited Consolidated Statements of Operations) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands		3 Months Ended																6 Months Ended		9 Months Ended		12 Months Ended
		Dec. 31, 2014	[1]	Sep. 30, 2014		Jun. 30, 2014		Mar. 31, 2014		Dec. 31, 2013		Sep. 30, 2013		Jun. 30, 2013		Mar. 31, 2013		Jun. 30, 2014		Sep. 30, 2014		Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Revenue		$ 1,231,300		$ 1,315,488		$ 1,107,232		$ 957,818		$ 1,159,100		$ 1,269,400		$ 977,600		$ 918,600		$ 2,065,050		$ 3,380,538		$ 4,611,803	$ 4,324,787	$ 3,726,789
Costs of revenue, excluding depreciation and amortization		1,063,100		1,122,861		950,715		841,324		987,000		1,081,100		822,700		791,500		1,792,040		2,914,901		3,977,963	3,682,367	3,239,195
Depreciation and amortization				41,747		36,755		33,494										70,249		111,996		154,452	140,926	91,958
General and administrative expenses				59,889		54,237		53,327										107,564		167,454		238,305	215,402	157,524
Interest expense, net				12,643		12,949		12,003										24,952		37,595		50,769	46,442	37,376
Other (income) expense, net				(1,416)		(1,923)		(2,083)										(4,007)		(5,424)		(8,116)	(6,188)	8,017
Income from continuing operations before income taxes				79,764		54,499		19,753										74,252		154,016		198,430	240,214	192,719
Provision for income taxes				(30,319)		(20,761)		(7,489)										(28,250)		(58,569)		(76,429)	(92,542)	(76,080)
Net income from continuing operations		26,600		49,445		33,738		12,264		42,900		49,900		35,500		19,300		46,002		95,447		122,001	147,672	116,639
Discontinued operations:
Net loss from discontinued operations		(5,900)		(320)		(149)		(122)		(1,300)		(3,700)		(500)		(900)		(272)		(592)		(6,452)	(6,456)	(9,223)
Net income				49,125		33,589		12,142										45,730		94,855		115,549	141,216	107,416
Net income (loss) attributable to non-controlling interests		(400)		139		(136)		45		100		100		100		0		(91)		48		(374)	266	(10)
Net income attributable to MasTec, Inc.		$ 21,100		$ 48,986		$ 33,725		$ 12,097		$ 41,500		$ 46,100		$ 34,900		$ 18,400		$ 45,821		$ 94,807		$ 115,923	$ 140,950	$ 107,426
Basic earnings (loss) per share:
Continuing operations (in dollars per share)		$ 0.33		$ 0.60		$ 0.43		$ 0.16		$ 0.55		$ 0.65		$ 0.46		$ 0.25		$ 0.59		$ 1.21		$ 1.53	$ 1.92	$ 1.49
Discontinued operations (in dollars per share)		(0.07)		0.00		0.00		0.00		(0.02)		(0.05)		(0.01)		(0.01)		0.00		(0.01)		(0.08)	(0.09)	(0.12)
Total basic earnings per share (in dollars per share)		0.26	[2]	$ 0.60	[2],[3]	$ 0.43	[2],[3]	$ 0.16	[2],[3]	0.54	[2]	0.60	[2]	0.46	[2]	0.24	[2]	$ 0.59	[3]	$ 1.20	[3]	$ 1.45	$ 1.83	$ 1.37
Basic weighted average common shares outstanding (in shares)				81,811		78,269		77,345										77,810		79,158		79,953	76,923	78,275
Diluted earnings (loss) per share:
Continuing operations (in dollars per share)		0.32		$ 0.57		$ 0.39		$ 0.14		0.50		0.59		0.42		0.23		$ 0.53		$ 1.11		$ 1.42	$ 1.74	$ 1.42
Discontinued operations (in dollars per share)		(0.07)		0.00		0.00		0.00		(0.02)		(0.04)		(0.01)		(0.01)		0.00		(0.01)		(0.07)	(0.08)	(0.11)
Total diluted earnings per share (in dollars per share)		$ 0.25	[2]	$ 0.57	[2],[3]	$ 0.39	[2],[3]	$ 0.14	[2],[3]	$ 0.49	[2]	$ 0.54	[2]	$ 0.41	[2]	$ 0.22	[2]	$ 0.53	[3]	$ 1.10	[3]	$ 1.35	$ 1.66	$ 1.31
Diluted weighted average common shares outstanding (in shares)				85,824		86,730		86,622										86,675		86,416		86,196	84,901	82,082
As Reported [Member]
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Revenue				$ 1,309,596		$ 1,104,556		$ 964,029										$ 2,068,585		$ 3,378,180
Costs of revenue, excluding depreciation and amortization				1,122,961		950,889		841,054										1,791,943		2,914,904
Depreciation and amortization				41,747		36,755		33,494										70,249		111,996
General and administrative expenses				59,889		54,237		53,327										107,564		167,454
Interest expense, net				12,643		12,949		12,003										24,952		37,595
Other (income) expense, net				(1,416)		(2,051)		(1,955)										(4,007)		(5,424)
Income from continuing operations before income taxes				73,772		51,777		26,106										77,884		151,655
Provision for income taxes				(28,042)		(19,714)		(9,916)										(29,630)		(57,671)
Net income from continuing operations				45,730		32,063		16,190										48,254		93,984
Discontinued operations:
Net loss from discontinued operations				(320)		(149)		(122)										(272)		(592)
Net income				45,410		31,914		16,068										47,982		93,392
Net income (loss) attributable to non-controlling interests				139		(136)		45										(91)		48
Net income attributable to MasTec, Inc.				$ 45,271		$ 32,050		$ 16,023										$ 48,073		$ 93,344
Basic earnings (loss) per share:
Continuing operations (in dollars per share)				$ 0.56		$ 0.41		$ 0.21										$ 0.62		$ 1.19
Discontinued operations (in dollars per share)				0.00		0.00		0.00										0.00		(0.01)
Total basic earnings per share (in dollars per share)	[3]			$ 0.55		$ 0.41		$ 0.21										$ 0.62		$ 1.18
Basic weighted average common shares outstanding (in shares)				81,811		78,269		77,345										77,810		79,158
Diluted earnings (loss) per share:
Continuing operations (in dollars per share)				$ 0.53		$ 0.37		$ 0.19										$ 0.56		$ 1.09
Discontinued operations (in dollars per share)				0.00		0.00		0.00										0.00		(0.01)
Total diluted earnings per share (in dollars per share)	[3]			$ 0.53		$ 0.37		$ 0.19										$ 0.56		$ 1.08
Diluted weighted average common shares outstanding (in shares)				85,824		86,730		86,622										86,675		86,416
Adjustments [Member]
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Revenue				$ 5,892		$ 2,676		$ (6,211)										$ (3,535)		$ 2,358
Costs of revenue, excluding depreciation and amortization				(100)		(174)		270										97		(3)
Depreciation and amortization				0		0		0										0		0
General and administrative expenses				0		0		0										0		0
Interest expense, net				0		0		0										0		0
Other (income) expense, net				0		128		(128)										0		0
Income from continuing operations before income taxes				5,992		2,722		(6,353)										(3,632)		2,361
Provision for income taxes				(2,277)		(1,047)		2,427										1,380		(898)
Net income from continuing operations				3,715		1,675		(3,926)										(2,252)		1,463
Discontinued operations:
Net loss from discontinued operations				0		0		0										0		0
Net income				3,715		1,675		(3,926)										(2,252)		1,463
Net income (loss) attributable to non-controlling interests				0		0		0										0		0
Net income attributable to MasTec, Inc.				$ 3,715		$ 1,675		$ (3,926)										$ (2,252)		$ 1,463
Basic earnings (loss) per share:
Continuing operations (in dollars per share)				$ 0.04		$ 0.02		$ (0.05)										$ (0.03)		$ 0.02
Discontinued operations (in dollars per share)				0.00		0.00		0.00										0.00		0.00
Total basic earnings per share (in dollars per share)	[3]			$ 0.05		$ 0.02		$ (0.05)										$ (0.03)		$ 0.02
Basic weighted average common shares outstanding (in shares)				0		0		0										0		0
Diluted earnings (loss) per share:
Continuing operations (in dollars per share)				$ 0.04		$ 0.02		$ (0.05)										$ (0.03)		$ 0.02
Discontinued operations (in dollars per share)				0.00		0.00		0.00										0.00		0.00
Total diluted earnings per share (in dollars per share)				$ 0.04	[3]	$ 0.02	[3]	$ (0.05)	[3]									$ (0.03)		$ 0.02	[3]
Diluted weighted average common shares outstanding (in shares)				0		0		0										0		0

[1] Preliminary, unaudited fourth quarter and full year 2014 results were previously issued pursuant to a press release dated February 26, 2015 and not previously filed in a report under the Securities Exchange Act of 1934, as amended. The unaudited quarterly information for the three month period ended December 31, 2014 in the table above includes the effect of adjustments determined by management following the review process described in Note 2 - Independent Investigation of the Audit Committee and Related Restatements.

[2] Earnings per share calculations, including the sum of the individual quarterly earnings per share amounts to the full year earnings per share amounts, may contain slight summation differences due to rounding.

[3] Earnings per share calculations may contain slight summation differences due to rounding.