Supplemental Guarantor Financial Information (Condensed Consolidating Statements Of Operations And Comprehensive Income) (Detail) (USD $)	3 Months Ended								12 Months Ended
	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Condensed Income Statements, Captions [Line Items]
Revenue	$ 1,159,100,000	$ 1,269,400,000	$ 977,600,000	$ 918,600,000	$ 932,400,000	$ 1,067,300,000	$ 988,900,000	$ 738,300,000	$ 4,324,787,000	$ 3,726,789,000	$ 2,831,292,000
Costs of revenue, excluding depreciation and amortization									3,682,367,000	3,239,195,000	2,459,746,000
Depreciation and amortization									140,928,000	92,601,000	75,228,000
General and administrative expenses									215,402,000	157,524,000	132,594,000
Interest expense, net									46,442,000	37,376,000	34,466,000
Loss on extinguishment of debt									5,624,000	0	0
Gain on remeasurement of equity interest in acquiree									0	0	(29,041,000)
Other expense (income), net									(6,188,000)	8,017,000	96,000
Income from continuing operations before income taxes									240,214,000	192,719,000	159,280,000
Benefit from (provision for) income taxes									(92,542,000)	(76,080,000)	(61,824,000)
Net income from continuing operations	42,900,000	49,900,000	35,500,000	19,300,000	37,700,000	36,100,000	31,200,000	11,700,000	147,672,000	116,639,000	97,456,000
Net (loss) income from discontinued operations	(1,300,000)	(3,700,000)	(500,000)	(900,000)	(1,400,000)	(9,300,000)	(1,100,000)	2,500,000	(6,456,000)	(9,223,000)	8,516,000
Equity in income from subsidiaries, net of tax									0	0	0
Net income									141,216,000	107,416,000	105,972,000
Net income (loss) attributable to non-controlling interests	100,000	100,000	100,000	0	0	0	0	0	266,000	(10,000)	(29,000)
Net income attributable to MasTec, Inc.	41,500,000	46,100,000	34,900,000	18,400,000	36,300,000	26,800,000	30,100,000	14,200,000	140,950,000	107,426,000	106,001,000
Comprehensive income (loss)									133,431,000	109,861,000	104,182,000
Continuing Operations [Member]
Condensed Income Statements, Captions [Line Items]
Depreciation and amortization									140,926,000	91,958,000	74,151,000
Interest expense, net									46,400,000	37,400,000	34,500,000
Consolidation, Eliminations [Member]
Condensed Income Statements, Captions [Line Items]
Revenue									(4,600,000)	(3,000,000)	(900,000)
Costs of revenue, excluding depreciation and amortization									(4,600,000)	(3,000,000)	(900,000)
General and administrative expenses									0	0	0
Interest expense, net									0	0	0
Loss on extinguishment of debt									0
Gain on remeasurement of equity interest in acquiree											0
Other expense (income), net									0	0	0
Income from continuing operations before income taxes									0	0	0
Benefit from (provision for) income taxes									0	0	0
Net income from continuing operations									0	0	0
Net (loss) income from discontinued operations									0	0	0
Equity in income from subsidiaries, net of tax									(142,200,000)	(108,400,000)	(107,500,000)
Net income									(142,200,000)	(108,400,000)	(107,500,000)
Net income (loss) attributable to non-controlling interests									0	0	0
Net income attributable to MasTec, Inc.									(142,200,000)	(108,400,000)	(107,500,000)
Comprehensive income (loss)									(134,400,000)	(108,400,000)	(107,500,000)
Consolidation, Eliminations [Member] | Continuing Operations [Member]
Condensed Income Statements, Captions [Line Items]
Depreciation and amortization									0	0	0
Parent Company [Member]
Condensed Income Statements, Captions [Line Items]
Revenue									0	0	0
Costs of revenue, excluding depreciation and amortization									0	0	0
General and administrative expenses									2,100,000	1,700,000	2,500,000
Interest expense, net									0	0	0
Loss on extinguishment of debt									0
Gain on remeasurement of equity interest in acquiree											0
Other expense (income), net									0	0	0
Income from continuing operations before income taxes									(2,100,000)	(1,700,000)	(2,500,000)
Benefit from (provision for) income taxes									800,000	700,000	1,000,000
Net income from continuing operations									(1,300,000)	(1,000,000)	(1,500,000)
Net (loss) income from discontinued operations									0	0	0
Equity in income from subsidiaries, net of tax									142,200,000	108,400,000	107,500,000
Net income									140,900,000	107,400,000	106,000,000
Net income (loss) attributable to non-controlling interests									0	0	0
Net income attributable to MasTec, Inc.									140,900,000	107,400,000	106,000,000
Comprehensive income (loss)									133,200,000	107,400,000	106,000,000
Parent Company [Member] | Continuing Operations [Member]
Condensed Income Statements, Captions [Line Items]
Depreciation and amortization									0	0	0
Guarantor Subsidiaries [Member]
Condensed Income Statements, Captions [Line Items]
Revenue									3,903,800,000	3,563,200,000	2,740,600,000
Costs of revenue, excluding depreciation and amortization									3,321,300,000	3,094,200,000	2,373,100,000
General and administrative expenses									184,600,000	147,400,000	125,800,000
Interest expense, net									45,500,000	37,400,000	34,400,000
Loss on extinguishment of debt									5,600,000
Gain on remeasurement of equity interest in acquiree											(29,000,000)
Other expense (income), net									(6,100,000)	7,800,000	100,000
Income from continuing operations before income taxes									232,800,000	187,400,000	164,200,000
Benefit from (provision for) income taxes									(91,900,000)	(75,600,000)	(64,400,000)
Net income from continuing operations									140,900,000	111,800,000	99,800,000
Net (loss) income from discontinued operations									0	0	0
Equity in income from subsidiaries, net of tax									0	0	0
Net income									140,900,000	111,800,000	99,800,000
Net income (loss) attributable to non-controlling interests									0	0	0
Net income attributable to MasTec, Inc.									140,900,000	111,800,000	99,800,000
Comprehensive income (loss)									140,900,000	112,400,000	99,600,000
Guarantor Subsidiaries [Member] | Continuing Operations [Member]
Condensed Income Statements, Captions [Line Items]
Depreciation and amortization									120,100,000	89,000,000	72,000,000
Non-Guarantor Subsidiaries [Member]
Condensed Income Statements, Captions [Line Items]
Revenue									425,600,000	166,600,000	91,600,000
Costs of revenue, excluding depreciation and amortization									365,700,000	148,000,000	87,500,000
General and administrative expenses									28,700,000	8,400,000	4,300,000
Interest expense, net									900,000	0	100,000
Loss on extinguishment of debt									0
Gain on remeasurement of equity interest in acquiree											0
Other expense (income), net									0	200,000	(100,000)
Income from continuing operations before income taxes									9,500,000	7,000,000	(2,400,000)
Benefit from (provision for) income taxes									(1,400,000)	(1,200,000)	1,600,000
Net income from continuing operations									8,100,000	5,800,000	(800,000)
Net (loss) income from discontinued operations									(6,500,000)	(9,200,000)	8,500,000
Equity in income from subsidiaries, net of tax									0	0	0
Net income									1,600,000	(3,400,000)	7,700,000
Net income (loss) attributable to non-controlling interests									300,000	0	0
Net income attributable to MasTec, Inc.									1,300,000	(3,400,000)	7,700,000
Comprehensive income (loss)									(6,200,000)	(1,500,000)	6,100,000
Non-Guarantor Subsidiaries [Member] | Continuing Operations [Member]
Condensed Income Statements, Captions [Line Items]
Depreciation and amortization									$ 20,800,000	$ 3,000,000	$ 2,200,000