Supplemental Guarantor Financial Information (Condensed Unaudited Consolidating Statements of Operations and Comprehensive Income) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Condensed Unaudited Consolidating Statements of Operations and Comprehensive Income [Line Items]
Revenue	$ 1,111,010	$ 1,315,488	$ 3,180,906	$ 3,380,538
Costs of revenue, excluding depreciation and amortization	972,711	1,122,861	2,805,072	2,914,901
Depreciation and amortization	42,196	41,747	128,048	111,996
General and administrative expenses	63,798	59,889	207,077	167,454
Interest expense (income), net	11,964	12,643	35,845	37,595
Other expense (income), net	6,702	(1,416)	4,342	(5,424)
Income from continuing operations before income taxes	13,639	79,764	522	154,016
Benefit from (provision for) income taxes	(6,197)	(30,319)	(3,288)	(58,569)
Net income (loss) from continuing operations	7,442	49,445	(2,766)	95,447
Net loss from discontinued operations	0	(320)	0	(592)
Equity in income (loss) from subsidiaries, net of tax	0	0	0	0
Net income (loss)	7,442	49,125	(2,766)	94,855
Net (loss) income attributable to non-controlling interests	(176)	139	(420)	48
Net income (loss) attributable to MasTec, Inc.	7,618	48,986	(2,346)	94,807
Comprehensive (loss) income	(5,888)	36,174	(34,816)	84,244
Reportable Legal Entities [Member] | MasTec, Inc. [Member]
Condensed Unaudited Consolidating Statements of Operations and Comprehensive Income [Line Items]
Revenue	0	0	0	0
Costs of revenue, excluding depreciation and amortization	0	0	0	0
Depreciation and amortization	0	0	0	0
General and administrative expenses	700	600	1,900	1,800
Interest expense (income), net	0	0	0	0
Other expense (income), net	0	0	0	0
Income from continuing operations before income taxes	(700)	(600)	(1,900)	(1,800)
Benefit from (provision for) income taxes	300	200	800	700
Net income (loss) from continuing operations	(400)	(400)	(1,100)	(1,100)
Net loss from discontinued operations		0		0
Equity in income (loss) from subsidiaries, net of tax	8,000	49,300	(1,300)	95,900
Net income (loss)	7,600	48,900	(2,400)	94,800
Net (loss) income attributable to non-controlling interests	0	0	0	0
Net income (loss) attributable to MasTec, Inc.	7,600	48,900	(2,400)	94,800
Comprehensive (loss) income	(5,700)	36,000	(34,400)	84,200
Reportable Legal Entities [Member] | Guarantor Subsidiaries [Member]
Condensed Unaudited Consolidating Statements of Operations and Comprehensive Income [Line Items]
Revenue	963,700	1,050,500	2,657,900	2,802,300
Costs of revenue, excluding depreciation and amortization	841,900	893,000	2,309,400	2,402,600
Depreciation and amortization	33,200	30,800	98,100	88,400
General and administrative expenses	57,000	50,800	184,900	146,700
Interest expense (income), net	27,700	11,500	82,900	35,600
Other expense (income), net	6,000	(1,700)	400	(5,900)
Income from continuing operations before income taxes	(2,100)	66,100	(17,800)	134,900
Benefit from (provision for) income taxes	1,300	(24,200)	7,900	(52,000)
Net income (loss) from continuing operations	(800)	41,900	(9,900)	82,900
Net loss from discontinued operations		0		0
Equity in income (loss) from subsidiaries, net of tax	0	0	0	0
Net income (loss)	(800)	41,900	(9,900)	82,900
Net (loss) income attributable to non-controlling interests	0	0	0	0
Net income (loss) attributable to MasTec, Inc.	(800)	41,900	(9,900)	82,900
Comprehensive (loss) income	(800)	41,900	(9,900)	83,000
Reportable Legal Entities [Member] | Non-Guarantor Subsidiaries [Member]
Condensed Unaudited Consolidating Statements of Operations and Comprehensive Income [Line Items]
Revenue	149,900	267,000	530,200	580,300
Costs of revenue, excluding depreciation and amortization	133,400	231,900	502,900	514,400
Depreciation and amortization	9,000	10,900	29,900	23,600
General and administrative expenses	6,100	8,500	20,300	19,000
Interest expense (income), net	(15,700)	1,100	(47,100)	2,000
Other expense (income), net	700	300	4,000	400
Income from continuing operations before income taxes	16,400	14,300	20,200	20,900
Benefit from (provision for) income taxes	(7,800)	(6,400)	(12,000)	(7,300)
Net income (loss) from continuing operations	8,600	7,900	8,200	13,600
Net loss from discontinued operations		(300)		(500)
Equity in income (loss) from subsidiaries, net of tax	0	0	0	0
Net income (loss)	8,600	7,600	8,200	13,100
Net (loss) income attributable to non-controlling interests	(200)	100	(500)	(100)
Net income (loss) attributable to MasTec, Inc.	8,800	7,500	8,700	13,200
Comprehensive (loss) income	(4,800)	(5,300)	(23,700)	2,400
Eliminations [Member]
Condensed Unaudited Consolidating Statements of Operations and Comprehensive Income [Line Items]
Revenue	(2,600)	(2,000)	(7,200)	(2,100)
Costs of revenue, excluding depreciation and amortization	(2,600)	(2,000)	(7,200)	(2,100)
Depreciation and amortization	0	0	0	0
General and administrative expenses	0	0	0	0
Interest expense (income), net	0	0	0	0
Other expense (income), net	0	0	0	0
Income from continuing operations before income taxes	0	0	0	0
Benefit from (provision for) income taxes	0	0	0	0
Net income (loss) from continuing operations	0	0	0	0
Net loss from discontinued operations		0		0
Equity in income (loss) from subsidiaries, net of tax	(8,000)	(49,300)	1,300	(95,900)
Net income (loss)	(8,000)	(49,300)	1,300	(95,900)
Net (loss) income attributable to non-controlling interests	0	0	0	0
Net income (loss) attributable to MasTec, Inc.	(8,000)	(49,300)	1,300	(95,900)
Comprehensive (loss) income	$ 5,400	$ (36,400)	$ 33,300	$ (85,300)