Supplemental Guarantor Financial Information (Condensed Consolidating Statements of Operations and Comprehensive Income (Loss)) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Condensed Consolidating Statements of Operations and Comprehensive Income (Loss) [Line Items]
Revenue	$ 1,341,900	$ 1,586,200	$ 1,232,400	$ 974,200	$ 1,027,400	$ 1,111,000	$ 1,066,600	$ 1,003,300	$ 5,134,703	$ 4,208,330	$ 4,611,803
Costs of revenue, excluding depreciation and amortization	1,120,600	1,369,000	1,068,200	884,400	916,300	972,700	945,900	886,400	4,442,125	3,721,303	3,977,963
Depreciation and amortization									164,915	169,662	154,452
Goodwill and intangible asset impairment									0	78,625	0
General and administrative expenses									261,433	265,910	238,305
Interest expense (income), net									50,734	48,055	50,769
Equity in (earnings) losses of unconsolidated affiliates									(3,528)	7,978	269
Other (income) expense, net									(6,795)	(15,457)	(8,385)
Income (loss) from continuing operations before income taxes									225,819	(67,746)	198,430
Benefit from (provision for) income taxes									(91,784)	(11,957)	(76,429)
Net income (loss) from continuing operations	55,900	56,500	24,400	(2,900)	(76,900)	7,400	(3,800)	(6,400)	134,035	(79,703)	122,001
Net loss from discontinued operations									0	0	(6,452)
Equity in income (loss) from subsidiaries, net of tax									0	0	0
Net income (loss)									134,035	(79,703)	115,549
Net income (loss) attributable to non-controlling interests									2,772	(593)	(374)
Net income (loss) attributable to MasTec, Inc.	$ 53,600	$ 56,300	$ 24,100	$ (2,700)	$ (76,700)	$ 7,600	$ (3,700)	$ (6,300)	131,263	(79,110)	115,923
Comprehensive income (loss)									140,572	(118,050)	94,831
Reportable Legal Entities [Member] | MasTec, Inc. [Member]
Condensed Consolidating Statements of Operations and Comprehensive Income (Loss) [Line Items]
Revenue									0	0	0
Costs of revenue, excluding depreciation and amortization									0	0	0
Depreciation and amortization									0	0	0
Goodwill and intangible asset impairment										0
General and administrative expenses									2,400	2,100	2,500
Interest expense (income), net									0	0	0
Equity in (earnings) losses of unconsolidated affiliates									0	0	0
Other (income) expense, net									0	0	0
Income (loss) from continuing operations before income taxes									(2,400)	(2,100)	(2,500)
Benefit from (provision for) income taxes									900	1,100	1,000
Net income (loss) from continuing operations									(1,500)	(1,000)	(1,500)
Net loss from discontinued operations											0
Equity in income (loss) from subsidiaries, net of tax									132,800	(78,100)	117,400
Net income (loss)									131,300	(79,100)	115,900
Net income (loss) attributable to non-controlling interests									0	0	0
Net income (loss) attributable to MasTec, Inc.									131,300	(79,100)	115,900
Comprehensive income (loss)									137,800	(117,500)	95,200
Reportable Legal Entities [Member] | Guarantor Subsidiaries [Member]
Condensed Consolidating Statements of Operations and Comprehensive Income (Loss) [Line Items]
Revenue									4,790,900	3,527,000	3,768,400
Costs of revenue, excluding depreciation and amortization									4,121,000	3,073,600	3,226,200
Depreciation and amortization									131,600	130,600	119,300
Goodwill and intangible asset impairment										0
General and administrative expenses									234,000	235,400	208,500
Interest expense (income), net									111,900	111,000	47,800
Equity in (earnings) losses of unconsolidated affiliates									0	0	0
Other (income) expense, net									0	(6,200)	(1,900)
Income (loss) from continuing operations before income taxes									192,400	(17,400)	168,500
Benefit from (provision for) income taxes									(66,800)	9,300	(70,600)
Net income (loss) from continuing operations									125,600	(8,100)	97,900
Net loss from discontinued operations											0
Equity in income (loss) from subsidiaries, net of tax									0	0	0
Net income (loss)									125,600	(8,100)	97,900
Net income (loss) attributable to non-controlling interests									0	0	0
Net income (loss) attributable to MasTec, Inc.									125,600	(8,100)	97,900
Comprehensive income (loss)									125,600	(8,100)	97,900
Reportable Legal Entities [Member] | Non-Guarantor Subsidiaries [Member]
Condensed Consolidating Statements of Operations and Comprehensive Income (Loss) [Line Items]
Revenue									407,000	689,700	847,700
Costs of revenue, excluding depreciation and amortization									384,300	656,100	756,100
Depreciation and amortization									33,300	39,100	35,200
Goodwill and intangible asset impairment										78,600
General and administrative expenses									25,000	28,400	27,300
Interest expense (income), net									(61,200)	(62,900)	3,000
Equity in (earnings) losses of unconsolidated affiliates									(3,500)	8,000	300
Other (income) expense, net									(6,800)	(9,300)	(6,600)
Income (loss) from continuing operations before income taxes									35,900	(48,300)	32,400
Benefit from (provision for) income taxes									(25,900)	(22,300)	(6,800)
Net income (loss) from continuing operations									10,000	(70,600)	25,600
Net loss from discontinued operations											(6,500)
Equity in income (loss) from subsidiaries, net of tax									0	0	0
Net income (loss)									10,000	(70,600)	19,100
Net income (loss) attributable to non-controlling interests									2,800	(600)	(400)
Net income (loss) attributable to MasTec, Inc.									7,200	(70,000)	19,500
Comprehensive income (loss)									16,500	(109,000)	(1,600)
Eliminations [Member]
Condensed Consolidating Statements of Operations and Comprehensive Income (Loss) [Line Items]
Revenue									(63,200)	(8,400)	(4,300)
Costs of revenue, excluding depreciation and amortization									(63,200)	(8,400)	(4,300)
Depreciation and amortization									0	0	0
Goodwill and intangible asset impairment										0
General and administrative expenses									0	0	0
Interest expense (income), net									0	0	0
Equity in (earnings) losses of unconsolidated affiliates									0	0	0
Other (income) expense, net									0	0	0
Income (loss) from continuing operations before income taxes									0	0	0
Benefit from (provision for) income taxes									0	0	0
Net income (loss) from continuing operations									0	0	0
Net loss from discontinued operations											0
Equity in income (loss) from subsidiaries, net of tax									(132,800)	78,100	(117,400)
Net income (loss)									(132,800)	78,100	(117,400)
Net income (loss) attributable to non-controlling interests									0	0	0
Net income (loss) attributable to MasTec, Inc.									(132,800)	78,100	(117,400)
Comprehensive income (loss)									$ (139,300)	$ 116,500	$ (96,700)