Supplemental Guarantor Financial Information (Condensed Unaudited Consolidating Balance Sheets) (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Assets
Total current assets	$ 1,267,099	$ 1,402,486
Property and equipment, net	570,479	549,084
Goodwill and other intangible assets, net	1,172,400	1,175,600
Investments in and advances to consolidated affiliates, net	0	0
Other long-term assets	105,842	55,977
Total assets	3,115,834	3,183,132
Liabilities and equity
Total current liabilities	813,260	839,990
Long-term debt	893,362	961,379
Other long-term liabilities	261,400	278,100
Total liabilities	1,968,028	2,079,498
Total equity	1,147,806	1,103,634
Total liabilities and equity	3,115,834	3,183,132
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	1,129,700	1,083,900
Other long-term assets	12,600	12,600
Total assets	1,142,300	1,096,500
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	1,142,300	1,096,500
Total liabilities and equity	1,142,300	1,096,500
Reportable Legal Entities [Member] | Guarantor Subsidiaries [Member]
Assets
Total current assets	1,116,000	1,256,300
Property and equipment, net	474,500	456,600
Goodwill and other intangible assets, net	1,034,400	1,037,400
Investments in and advances to consolidated affiliates, net	716,000	625,900
Other long-term assets	26,300	25,300
Total assets	3,367,200	3,401,500
Liabilities and equity
Total current liabilities	742,500	759,700
Long-term debt	874,000	938,700
Other long-term liabilities	249,600	256,200
Total liabilities	1,866,100	1,954,600
Total equity	1,501,100	1,446,900
Total liabilities and equity	3,367,200	3,401,500
Reportable Legal Entities [Member] | Non-Guarantor Subsidiaries [Member]
Assets
Total current assets	194,700	175,800
Property and equipment, net	96,000	92,500
Goodwill and other intangible assets, net	138,000	138,200
Investments in and advances to consolidated affiliates, net	820,900	861,200
Other long-term assets	66,900	18,000
Total assets	1,316,500	1,285,700
Liabilities and equity
Total current liabilities	114,400	109,900
Long-term debt	19,400	22,700
Other long-term liabilities	11,800	21,900
Total liabilities	145,600	154,500
Total equity	1,170,900	1,131,200
Total liabilities and equity	1,316,500	1,285,700
Eliminations [Member]
Assets
Total current assets	(43,600)	(29,600)
Property and equipment, net	0	0
Goodwill and other intangible assets, net	0	0
Investments in and advances to consolidated affiliates, net	(2,666,600)	(2,571,000)
Other long-term assets	0	0
Total assets	(2,710,200)	(2,600,600)
Liabilities and equity
Total current liabilities	(43,600)	(29,600)
Long-term debt	0	0
Other long-term liabilities	0	0
Total liabilities	(43,600)	(29,600)
Total equity	(2,666,600)	(2,571,000)
Total liabilities and equity	$ (2,710,200)	$ (2,600,600)