Supplemental Guarantor Financial Information (Condensed Consolidating Balance Sheets) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Assets
Total current assets	$ 1,402,486	$ 1,129,758
Property and equipment, net	549,084	558,667
Goodwill and other intangible assets, net	1,175,600	1,187,900
Investments in and advances to consolidated affiliates, net	0	0
Other long-term assets	55,977	51,032
Total assets	3,183,132	2,927,347	$ 3,550,800
Liabilities and equity
Total current liabilities	839,990	752,535
Long-term debt	961,379	932,868
Other long-term liabilities	278,100	298,500
Total liabilities	2,079,498	1,983,956
Total equity	1,103,634	943,391	$ 1,148,075	$ 1,021,058
Total liabilities and equity	3,183,132	2,927,347
Reportable Legal Entities [Member] | MasTec, Inc. [Member]
Assets
Total current assets	0	0
Property and equipment, net	0	0
Goodwill and other intangible assets, net	0	0
Investments in and advances to consolidated affiliates, net	1,083,900	930,300
Other long-term assets	12,600	9,300
Total assets	1,096,500	939,600
Liabilities and equity
Total current liabilities	0	0
Long-term debt	0	0
Other long-term liabilities	0	0
Total liabilities	0	0
Total equity	1,096,500	939,600
Total liabilities and equity	1,096,500	939,600
Reportable Legal Entities [Member] | Guarantor Subsidiaries [Member]
Assets
Total current assets	1,256,300	927,400
Property and equipment, net	456,600	448,200
Goodwill and other intangible assets, net	1,037,400	1,047,500
Investments in and advances to consolidated affiliates, net	625,900	527,200
Other long-term assets	25,300	24,300
Total assets	3,401,500	2,974,600
Liabilities and equity
Total current liabilities	759,700	632,900
Long-term debt	938,700	900,100
Other long-term liabilities	256,200	275,600
Total liabilities	1,954,600	1,808,600
Total equity	1,446,900	1,166,000
Total liabilities and equity	3,401,500	2,974,600
Reportable Legal Entities [Member] | Non-Guarantor Subsidiaries [Member]
Assets
Total current assets	175,800	202,400
Property and equipment, net	92,500	110,500
Goodwill and other intangible assets, net	138,200	140,400
Investments in and advances to consolidated affiliates, net	861,200	930,000
Other long-term assets	18,000	17,300
Total assets	1,285,700	1,400,600
Liabilities and equity
Total current liabilities	109,900	119,600
Long-term debt	22,700	32,800
Other long-term liabilities	21,900	23,000
Total liabilities	154,500	175,400
Total equity	1,131,200	1,225,200
Total liabilities and equity	1,285,700	1,400,600
Eliminations [Member]
Assets
Total current assets	(29,600)	0
Property and equipment, net	0	0
Goodwill and other intangible assets, net	0	0
Investments in and advances to consolidated affiliates, net	(2,571,000)	(2,387,500)
Other long-term assets	0	0
Total assets	(2,600,600)	(2,387,500)
Liabilities and equity
Total current liabilities	(29,600)	0
Long-term debt	0	0
Other long-term liabilities	0	0
Total liabilities	(29,600)	0
Total equity	(2,571,000)	(2,387,500)
Total liabilities and equity	$ (2,600,600)	$ (2,387,500)