Supplemental Guarantor Financial Information (Condensed Unaudited Consolidating Balance Sheets) (Details) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Assets
Total current assets	$ 1,790,707	$ 1,402,486
Property and equipment, net	648,456	549,084
Goodwill and other intangible assets, net	1,226,200	1,175,600
Investments in and advances to consolidated affiliates, net	0	0
Other long-term assets	158,088	55,977
Total assets	3,823,485	3,183,132
Liabilities and equity
Total current liabilities	928,731	839,990
Long-term debt	1,313,860	961,379
Other long-term liabilities	347,700	278,100
Total liabilities	2,590,323	2,079,498
Total equity	1,233,162	1,103,634
Total liabilities and equity	3,823,485	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	1,212,900	1,083,900
Other long-term assets	13,100	12,600
Total assets	1,226,000	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	1,226,000	1,096,500
Total liabilities and equity	1,226,000	1,096,500
Reportable Legal Entities [Member] | Guarantor Subsidiaries [Member]
Assets
Total current assets	1,649,500	1,256,300
Property and equipment, net	556,100	456,600
Goodwill and other intangible assets, net	1,086,400	1,037,400
Investments in and advances to consolidated affiliates, net	806,200	625,900
Other long-term assets	23,000	25,300
Total assets	4,121,200	3,401,500
Liabilities and equity
Total current liabilities	902,400	759,700
Long-term debt	1,299,500	938,700
Other long-term liabilities	335,600	256,200
Total liabilities	2,537,500	1,954,600
Total equity	1,583,700	1,446,900
Total liabilities and equity	4,121,200	3,401,500
Reportable Legal Entities [Member] | Non-Guarantor Subsidiaries [Member]
Assets
Total current assets	212,800	175,800
Property and equipment, net	92,400	92,500
Goodwill and other intangible assets, net	139,800	138,200
Investments in and advances to consolidated affiliates, net	749,000	861,200
Other long-term assets	122,000	18,000
Total assets	1,316,000	1,285,700
Liabilities and equity
Total current liabilities	97,900	109,900
Long-term debt	14,400	22,700
Other long-term liabilities	12,100	21,900
Total liabilities	124,400	154,500
Total equity	1,191,600	1,131,200
Total liabilities and equity	1,316,000	1,285,700
Eliminations [Member]
Assets
Total current assets	(71,600)	(29,600)
Property and equipment, net	0	0
Goodwill and other intangible assets, net	0	0
Investments in and advances to consolidated affiliates, net	(2,768,100)	(2,571,000)
Other long-term assets	0	0
Total assets	(2,839,700)	(2,600,600)
Liabilities and equity
Total current liabilities	(71,600)	(29,600)
Long-term debt	0	0
Other long-term liabilities	0	0
Total liabilities	(71,600)	(29,600)
Total equity	(2,768,100)	(2,571,000)
Total liabilities and equity	$ (2,839,700)	$ (2,600,600)