Supplemental Guarantor Financial Information (Condensed Consolidating Statements Of Operations And Comprehensive Income) (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended								12 Months Ended
	Dec. 31, 2012	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Condensed Financial Statements, Captions [Line Items]
Revenue	$ 932,300	$ 1,067,300	$ 988,900	$ 738,300	$ 731,600	$ 816,200	$ 709,900	$ 573,600	$ 3,726,789	$ 2,831,292	$ 2,143,024
Costs of revenue, excluding depreciation and amortization									3,239,195	2,459,746	1,829,498
Depreciation and amortization									92,601	75,228	57,966
General and administrative expenses									157,524	132,594	112,180
Interest expense, net									37,376	34,466
Gain on remeasurement of equity interest in acquiree									0	(29,041)	0
Other expense (income), net									8,017	96	1,219
Income from continuing operations before provision for income taxes									192,719	159,280	114,072
Benefit (provision) for income taxes									(76,080)	(61,824)	(47,942)
Income from continuing operations before non-controlling interests	37,600	36,100	31,200	11,700	7,000	30,800	43,400	16,300	116,639	97,456	66,130
Income (loss) from discontinued operations, net of tax	(1,300)	(9,300)	(1,100)	2,500	1,600	1,000	1,100	4,800	(9,223)	8,516	24,257
Equity in income from subsidiaries, net of tax									0	0
Net income									107,416	105,972	90,387
Net loss attributable to non-controlling interests									(10)	(29)	(141)
Net income attributable to MasTec, Inc.	36,300	26,800	30,100	14,200	8,600	31,800	44,500	21,100	107,426	106,001	90,528
Comprehensive income (loss)									109,861	104,182	90,355
Parent Company [Member]
Condensed Financial Statements, Captions [Line Items]
Revenue									0	0
Costs of revenue, excluding depreciation and amortization									0	0
General and administrative expenses									1,665	2,530
Interest expense, net									0	0
Gain on remeasurement of equity interest in acquiree										0
Other expense (income), net									0	0
Income from continuing operations before provision for income taxes									(1,667)	(2,530)
Benefit (provision) for income taxes									675	989
Income from continuing operations before non-controlling interests									(992)	(1,541)
Income (loss) from discontinued operations, net of tax									0	0
Equity in income from subsidiaries, net of tax									108,408	107,513
Net income									107,416	105,972
Net loss attributable to non-controlling interests									0	0
Net income attributable to MasTec, Inc.									107,416	105,972
Comprehensive income (loss)									107,416	105,972
Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Revenue									3,538,288	2,726,618
Costs of revenue, excluding depreciation and amortization									3,074,031	2,360,578
General and administrative expenses									145,831	125,136
Interest expense, net									37,378	34,391
Gain on remeasurement of equity interest in acquiree										(29,041)
Other expense (income), net									7,838	224
Income from continuing operations before provision for income taxes									183,584	163,425
Benefit (provision) for income taxes									(74,440)	(64,395)
Income from continuing operations before non-controlling interests									109,144	99,030
Income (loss) from discontinued operations, net of tax									(7,390)	10,007
Equity in income from subsidiaries, net of tax									0	0
Net income									101,754	109,037
Net loss attributable to non-controlling interests									0	0
Net income attributable to MasTec, Inc.									101,754	109,037
Comprehensive income (loss)									102,275	108,877
Non-Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Revenue									188,501	104,674
Costs of revenue, excluding depreciation and amortization									165,164	99,168
General and administrative expenses									10,028	4,928
Interest expense, net									(2)	75
Gain on remeasurement of equity interest in acquiree										0
Other expense (income), net									179	(128)
Income from continuing operations before provision for income taxes									10,802	(1,615)
Benefit (provision) for income taxes									(2,315)	1,582
Income from continuing operations before non-controlling interests									8,487	(33)
Income (loss) from discontinued operations, net of tax									(1,833)	(1,491)
Equity in income from subsidiaries, net of tax									0	0
Net income									6,654	(1,524)
Net loss attributable to non-controlling interests									(10)	(29)
Net income attributable to MasTec, Inc.									6,664	(1,495)
Comprehensive income (loss)									8,578	(3,154)
Consolidation, Eliminations [Member]
Condensed Financial Statements, Captions [Line Items]
Revenue									0	0
Costs of revenue, excluding depreciation and amortization									0	0
General and administrative expenses									0	0
Interest expense, net									0	0
Gain on remeasurement of equity interest in acquiree										0
Other expense (income), net									0	0
Income from continuing operations before provision for income taxes									0	0
Benefit (provision) for income taxes									0	0
Income from continuing operations before non-controlling interests									0	0
Income (loss) from discontinued operations, net of tax									0	0
Equity in income from subsidiaries, net of tax									(108,408)	(107,513)
Net income									(108,408)	(107,513)
Net loss attributable to non-controlling interests									0	0
Net income attributable to MasTec, Inc.									(108,408)	(107,513)
Comprehensive income (loss)									(108,408)	(107,513)
Segment, Continuing Operations [Member]
Condensed Financial Statements, Captions [Line Items]
Revenue									3,726,800	2,831,300	2,143,000
Depreciation and amortization									91,958	74,151	56,877
Segment, Continuing Operations [Member] | Parent Company [Member]
Condensed Financial Statements, Captions [Line Items]
Depreciation and amortization									2	0
Segment, Continuing Operations [Member] | Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Depreciation and amortization									89,626	71,905
Segment, Continuing Operations [Member] | Non-Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Depreciation and amortization									2,330	2,246
Segment, Continuing Operations [Member] | Consolidation, Eliminations [Member]
Condensed Financial Statements, Captions [Line Items]
Depreciation and amortization									$ 0	$ 0