Supplemental Guarantor Financial Information (Condensed Unaudited Consolidating Statements Of Cash Flows) (Detail) (USD $)	6 Months Ended
	Jun. 30, 2013	Jun. 30, 2012
Condensed Financial Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	$ 14,567,000	$ (4,244,000)
Cash flows (used in) provided by investing activities:
Cash paid for acquisitions, net, including contingent consideration	(133,392,000)	(15,862,000)
Capital expenditures	(71,382,000)	(28,490,000)
Proceeds from sale of property and equipment	18,978,000	3,808,000
Proceeds from sale or redemption of investments	5,025,000	0
Proceeds from disposal of business, net	0	97,728,000
Investments in life insurance policies	(94,000)	(284,000)
Net cash (used in) provided by investing activities	(180,865,000)	56,900,000
Cash flows provided by (used in) financing activities:
Proceeds from issuance of 4.875% senior notes	400,000,000	0
Repayment of 7.625% senior notes	(150,000,000)	0
Proceeds from credit facility	499,666,000	422,550,000
Repayments of credit facility	(558,596,000)	(418,750,000)
Repayments of other borrowings	(18,570,000)	(10,542,000)
(Repayments of) proceeds from book overdrafts	7,989,000	(5,290,000)
Payments of capital lease obligations	(21,139,000)	(9,668,000)
Proceeds from stock option exercises and other share-based awards	4,283,000	766,000
Excess tax benefit from stock-based compensation	1,462,000	70,000
Purchases of treasury stock	0	(35,087,000)
Payments for debt extinguishment, call premiums	(4,116,000)	0
Payments of financing costs	(7,569,000)	(115,000)
Net financing activities and advances (to) from consolidated affiliates	0	0
Net cash provided by (used in) financing activities	153,410,000	(56,066,000)
Net decrease in cash and cash equivalents	(12,888,000)	(3,410,000)
Net effect of currency translation on cash	(274,000)	(56,000)
Cash and cash equivalents - beginning of period	26,767,000	20,280,000
Cash and cash equivalents - end of period	13,605,000	16,814,000
Cash and cash equivalents of discontinued operations	310,000	386,000
Cash and cash equivalents of continuing operations	13,295,000	16,428,000
MasTec, Inc. [Member]
Condensed Financial Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	(941,000)	(697,000)
Cash flows (used in) provided by investing activities:
Cash paid for acquisitions, net, including contingent consideration	0	0
Capital expenditures	0	0
Proceeds from sale of property and equipment	0	0
Proceeds from sale or redemption of investments	0
Proceeds from disposal of business, net		0
Investments in life insurance policies	0	(284,000)
Net cash (used in) provided by investing activities	0	(284,000)
Cash flows provided by (used in) financing activities:
Proceeds from issuance of 4.875% senior notes	0
Repayment of 7.625% senior notes	0
Proceeds from credit facility	0	0
Repayments of credit facility	0	0
Repayments of other borrowings	0	0
(Repayments of) proceeds from book overdrafts	0	0
Payments of capital lease obligations	0	0
Proceeds from stock option exercises and other share-based awards	4,283,000	766,000
Excess tax benefit from stock-based compensation	0	0
Purchases of treasury stock		(35,087,000)
Payments for debt extinguishment, call premiums	0
Payments of financing costs	0	0
Net financing activities and advances (to) from consolidated affiliates	(3,233,000)	35,302,000
Net cash provided by (used in) financing activities	1,050,000	981,000
Net decrease in cash and cash equivalents	109,000	0
Net effect of currency translation on cash	0	0
Cash and cash equivalents - beginning of period	0	0
Cash and cash equivalents - end of period	109,000	0
Cash and cash equivalents of discontinued operations	0	0
Cash and cash equivalents of continuing operations	109,000	0
Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	57,365,000	20,091,000
Cash flows (used in) provided by investing activities:
Cash paid for acquisitions, net, including contingent consideration	(26,202,000)	(15,862,000)
Capital expenditures	(70,335,000)	(27,625,000)
Proceeds from sale of property and equipment	18,884,000	3,808,000
Proceeds from sale or redemption of investments	5,025,000
Proceeds from disposal of business, net		97,728,000
Investments in life insurance policies	(94,000)	0
Net cash (used in) provided by investing activities	(72,722,000)	58,049,000
Cash flows provided by (used in) financing activities:
Proceeds from issuance of 4.875% senior notes	400,000,000
Repayment of 7.625% senior notes	(150,000,000)
Proceeds from credit facility	461,941,000	422,550,000
Repayments of credit facility	(524,358,000)	(418,750,000)
Repayments of other borrowings	(18,570,000)	(10,542,000)
(Repayments of) proceeds from book overdrafts	7,989,000	(5,290,000)
Payments of capital lease obligations	(20,900,000)	(9,649,000)
Proceeds from stock option exercises and other share-based awards	0	0
Excess tax benefit from stock-based compensation	1,462,000	70,000
Purchases of treasury stock		0
Payments for debt extinguishment, call premiums	(4,116,000)
Payments of financing costs	(7,569,000)	(115,000)
Net financing activities and advances (to) from consolidated affiliates	(143,781,000)	(63,813,000)
Net cash provided by (used in) financing activities	2,098,000	(85,539,000)
Net decrease in cash and cash equivalents	(13,259,000)	(7,399,000)
Net effect of currency translation on cash	0	(114,000)
Cash and cash equivalents - beginning of period	17,829,000	16,242,000
Cash and cash equivalents - end of period	4,570,000	8,729,000
Cash and cash equivalents of discontinued operations	190,000	105,000
Cash and cash equivalents of continuing operations	4,380,000	8,624,000
Non-Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	(41,857,000)	(23,638,000)
Cash flows (used in) provided by investing activities:
Cash paid for acquisitions, net, including contingent consideration	(107,190,000)	0
Capital expenditures	(1,047,000)	(865,000)
Proceeds from sale of property and equipment	94,000	0
Proceeds from sale or redemption of investments	0
Proceeds from disposal of business, net		0
Investments in life insurance policies	0	0
Net cash (used in) provided by investing activities	(108,143,000)	(865,000)
Cash flows provided by (used in) financing activities:
Proceeds from issuance of 4.875% senior notes	0
Repayment of 7.625% senior notes	0
Proceeds from credit facility	37,725,000	0
Repayments of credit facility	(34,238,000)	0
Repayments of other borrowings	0	0
(Repayments of) proceeds from book overdrafts	0	0
Payments of capital lease obligations	(239,000)	(19,000)
Proceeds from stock option exercises and other share-based awards	0	0
Excess tax benefit from stock-based compensation	0	0
Purchases of treasury stock		0
Payments for debt extinguishment, call premiums	0
Payments of financing costs	0	0
Net financing activities and advances (to) from consolidated affiliates	147,014,000	28,511,000
Net cash provided by (used in) financing activities	150,262,000	28,492,000
Net decrease in cash and cash equivalents	262,000	3,989,000
Net effect of currency translation on cash	(274,000)	58,000
Cash and cash equivalents - beginning of period	8,938,000	4,038,000
Cash and cash equivalents - end of period	8,926,000	8,085,000
Cash and cash equivalents of discontinued operations	120,000	281,000
Cash and cash equivalents of continuing operations	8,806,000	7,804,000
Consolidation, Eliminations [Member]
Condensed Financial Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	0	0
Cash flows (used in) provided by investing activities:
Cash paid for acquisitions, net, including contingent consideration	0	0
Capital expenditures	0	0
Proceeds from sale of property and equipment	0	0
Proceeds from sale or redemption of investments	0
Proceeds from disposal of business, net		0
Investments in life insurance policies	0	0
Net cash (used in) provided by investing activities	0	0
Cash flows provided by (used in) financing activities:
Proceeds from issuance of 4.875% senior notes	0
Repayment of 7.625% senior notes	0
Proceeds from credit facility	0	0
Repayments of credit facility	0	0
Repayments of other borrowings	0	0
(Repayments of) proceeds from book overdrafts	0	0
Payments of capital lease obligations	0	0
Proceeds from stock option exercises and other share-based awards	0	0
Excess tax benefit from stock-based compensation	0	0
Purchases of treasury stock		0
Payments for debt extinguishment, call premiums	0
Payments of financing costs	0	0
Net financing activities and advances (to) from consolidated affiliates	0	0
Net cash provided by (used in) financing activities	0	0
Net decrease in cash and cash equivalents	0	0
Net effect of currency translation on cash	0	0
Cash and cash equivalents - beginning of period	0	0
Cash and cash equivalents - end of period	0	0
Cash and cash equivalents of discontinued operations	0	0
Cash and cash equivalents of continuing operations	$ 0	$ 0