MasTec (MTZ) 10-Q 1 May 14 2014 Q1 Quarterly report Financial data

Document_and_Entity_Informatio

Document and Entity Information	3 Months Ended
	Mar. 31, 2014	Apr. 28, 2014
Document and Entity Information [Abstract]	'	'
Document Type	'10-Q	'
Amendment Flag	'false	'
Document Period End Date	31-Mar-14	'
Document Fiscal Year Focus	'2014	'
Document Fiscal Period Focus	'Q1	'
Entity Registrant Name	'MASTEC INC	'
Trading Symbol	'MTZ	'
Entity Central Index Key	'0000015615	'
Current Fiscal Year End Date	'--12-31	'
Entity Current Reporting Status	'Yes	'
Entity Filer Category	'Large Accelerated Filer	'
Entity Common Stock, Shares Outstanding	'	77,556,250

Condensed_Unaudited_Consolidat

Condensed Unaudited Consolidated Statements Of Operations (USD $)	3 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Mar. 31, 2014		Mar. 31, 2013
Income Statement [Abstract]	'		'
Revenue	$964,029		$918,648
Costs of revenue, excluding depreciation and amortization	841,054		791,499
Depreciation and amortization	33,494		31,753
General and administrative expenses	53,327		48,885
Interest expense, net	12,003		10,045
Loss on extinguishment of debt	0		5,624
Other income, net	-1,955		-826
Income from continuing operations before income taxes	26,106		31,668
Provision for income taxes	-9,916		-12,348
Net income from continuing operations	16,190		19,320
Discontinued operations:	'		'
Net loss from discontinued operations (See Note 4)	-122		-947
Net income	16,068		18,373
Net income attributable to non-controlling interests	45		3
Net income attributable to MasTec, Inc.	$16,023		$18,370
Basic earnings (loss) per share:	'		'
Continuing operations	$0.21		$0.25
Discontinued operations	$0		($0.01)
Total basic earnings per share	$0.21	[1]	$0.24	[1]
Basic weighted average common shares outstanding	77,345		76,608
Diluted earnings (loss) per share:	'		'
Continuing operations	$0.19		$0.23
Discontinued operations	$0		($0.01)
Total diluted earnings per share	$0.19	[1]	$0.22	[1]
Diluted weighted average common shares outstanding	86,622		84,094
[1]	Earnings per share calculations may contain slight summation differences due to rounding.

Condensed_Unaudited_Consolidat1

Condensed Unaudited Consolidated Statements Of Comprehensive Income (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Net income	$16,068	$18,373
Other comprehensive (loss) income:	'	'
Activity, net of tax (See Note 13)	-5,335	-603
Comprehensive income	10,733	17,770
Comprehensive income attributable to non-controlling interests	45	3
Comprehensive income attributable to MasTec, Inc.	10,688	17,767
Foreign Currency [Member]	'	'
Other comprehensive (loss) income:	'	'
Activity, net of tax (See Note 13)	-5,335	-824
Available-for-Sale-Securities [Member]	'	'
Other comprehensive (loss) income:	'	'
Activity, net of tax (See Note 13)	$0	$221

Condensed_Unaudited_Consolidat2

Condensed Unaudited Consolidated Balance Sheets (USD $)	Mar. 31, 2014	Dec. 31, 2013
Current assets:	'	'
Cash and cash equivalents	$9,261,000	$22,927,000
Accounts receivable, net of allowance	1,195,603,000	1,134,577,000
Inventories, net	89,146,000	70,185,000
Prepaid expenses and other current assets, including discontinued operations (See Note 4)	63,926,000	78,534,000
Total current assets	1,357,936,000	1,306,223,000
Property and equipment, net	509,585,000	488,132,000
Goodwill	912,885,000	900,454,000
Other intangible assets, net	171,562,000	165,606,000
Other long-term assets, including discontinued operations (See Note 4)	61,439,000	60,552,000
Total assets	3,013,407,000	2,920,967,000
Current liabilities:	'	'
Current maturities of long-term debt	52,949,000	51,376,000
Accounts payable	440,152,000	424,917,000
Accrued salaries and wages	68,055,000	66,455,000
Other accrued expenses	60,581,000	71,448,000
Billings in excess of costs and earnings	109,370,000	121,641,000
Other current liabilities, including discontinued operations (See Note 4)	24,588,000	26,162,000
Total current liabilities	820,389,000	826,746,000
Long-term debt	841,335,000	765,425,000
Long-term deferred tax liabilities, net	154,151,000	155,012,000
Other liabilities	40,929,000	40,357,000
Total liabilities	1,976,560,000	1,899,910,000
Commitments and contingencies (See Note 16)	'	'
Equity:	'	'
Preferred stock, $1.00 par value; authorized shares - 5,000,000; issued and outstanding shares - none	0	0
Common stock, $0.10 par value; authorized shares - 145,000,000; issued shares - 86,993,988 and 86,725,372 as of March 31, 2014 and December 31, 2013, respectively	8,700,000	8,672,000
Capital surplus	827,863,000	822,836,000
Retained earnings	357,887,000	341,864,000
Accumulated other comprehensive loss	-18,621,000	-13,286,000
Treasury stock, at cost; 9,467,286 shares as of both March 31, 2014 and December 31, 2013	-150,000,000	-150,000,000
Total MasTec, Inc. shareholders' equity	1,031,831,000	1,016,088,000
Non-controlling interests	5,016,000	4,969,000
Total equity	1,036,847,000	1,021,057,000
Total liabilities and equity	3,013,407,000	2,920,967,000
Investor [Member] | Contributed Shares [Member]	'	'
Equity:	'	'
Contributed shares (See Note 11)	6,002,000	6,002,000
Earn-out Arrangements [Member]	'	'
Current liabilities:	'	'
Acquisition-related contingent consideration, current	64,694,000	64,747,000
Acquisition-related contingent consideration, net of current portion	$119,756,000	$112,370,000

Condensed_Unaudited_Consolidat3

Condensed Unaudited Consolidated Balance Sheets (Parenthetical) (USD $)	Mar. 31, 2014	Dec. 31, 2013
Statement of Financial Position [Abstract]	'	'
Preferred stock, par value	$1	$1
Preferred stock, shares authorized	5,000,000	5,000,000
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value	$0.10	$0.10
Common stock, shares authorized	145,000,000	145,000,000
Common stock, shares issued	86,993,988	86,725,372
Treasury stock, shares	9,467,286	9,467,286

Condensed_Unaudited_Consolidat4

Condensed Unaudited Consolidated Statements Of Cash Flows (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2014		Mar. 31, 2013
Cash flows from operating activities:	'		'
Net income	$16,068		$18,373
Adjustments to reconcile net income to net cash (used in) provided by operating activities:	'		'
Depreciation and amortization	33,494		31,753
Non-cash interest expense, including write-off of deferred financing costs on redeemed debt	2,362		3,747
Non-cash stock-based compensation expense	3,260		2,357
Excess tax benefit from stock-based compensation	-3,246	[1]	-903	[1]
Provision for deferred income taxes	3,281		-3,626
(Gains) losses on sales of assets	-1,622		-683
Changes in assets and liabilities, net of acquisitions:	'		'
Accounts receivable	-43,440		-28,497
Inventories	-13,313		12,167
Other assets, current and non-current portion	9,034		6,978
Accounts payable and accrued expenses	-14,683		-4,844
Billings in excess of costs and earnings	-12,247		-19,596
Book overdrafts	1,266		-5,970
Other liabilities, current and non-current portion	-1,339		11,542
Net cash (used in) provided by operating activities	-20,394		26,130
Cash flows (used in) provided by investing activities:	'		'
Cash paid for acquisitions, net of cash acquired	-23,831		-4,653
Capital expenditures	-35,554		-25,851
Proceeds from sale of property and equipment	3,373		3,411
Payments for other investments	-1,098		0
Net cash used in investing activities	-57,110		-27,093
Cash flows provided by (used in) financing activities:	'		'
Proceeds from credit facility	233,872		231,600
Repayments of credit facility	-157,349		-365,600
Proceeds from issuance of senior notes	0		400,000
Repayment of senior notes	0		-150,000
Repayments of other borrowings	-2,830		-11,429
Payments of capital lease obligations	-10,956		-7,692
Excess tax benefit from stock-based compensation	3,246		903
Payments of financing costs, including call premiums on extinguishment of debt	-218		-10,968
Net cash provided by financing activities	64,314		84,365
Net (decrease) increase in cash and cash equivalents	-13,190		83,402
Net effect of currency translation on cash	-476		-60
Cash and cash equivalents - beginning of period	22,927		26,767
Cash and cash equivalents - end of period	9,261		110,109
Cash and cash equivalents of discontinued operations	0		862
Cash and cash equivalents of continuing operations	9,261		109,247
Supplemental cash flow information:	'		'
Interest paid	12,430		10,720
Income taxes paid, net of refunds	11,928		8,245
Supplemental disclosure of non-cash information:	'		'
Equipment acquired under capital lease	8,240		23,002
Equipment [Member]	'		'
Supplemental disclosure of non-cash information:	'		'
Equipment acquired under financing arrangements	5,780		14,569
Earn-out Arrangements [Member]	'		'
Cash flows provided by (used in) financing activities:	'		'
Payments of acquisition-related contingent consideration	0		-5,003
Supplemental disclosure of non-cash information:	'		'
Value of acquisition-related contingent consideration	8,700		0
Stock Compensation Plan [Member]	'		'
Cash flows provided by (used in) financing activities:	'		'
Payments of tax withholdings and proceeds from stock-based awards, net	-1,451		2,554
Payments of acquisition-related contingent consideration	1,800		3,500
Operating Expense [Member]	'		'
Adjustments to reconcile net income to net cash (used in) provided by operating activities:	'		'
Provision for losses on operating assets	623		3,584
Contracts Accounted for under Percentage of Completion [Member]	'		'
Adjustments to reconcile net income to net cash (used in) provided by operating activities:	'		'
Provision for losses on construction projects, net	$108		($252)
[1]	Excess tax benefits, which represent cash flows from tax deductions in excess of the recorded tax effect of compensation expense recognized for stock options exercised and vested restricted shares, are classified as financing cash flows in the Company’s condensed unaudited consolidated statements of cash flows.

Business_Basis_of_Presentation

Business, Basis of Presentation and Significant Accounting Policies	3 Months Ended
	Mar. 31, 2014
Accounting Policies [Abstract]	'
Business, Basis of Presentation and Significant Accounting Policies	'
	Business, Basis of Presentation and Significant Accounting Policies
	Nature of the Business
	MasTec, Inc. (collectively with its subsidiaries, “MasTec” or the “Company”) is a leading infrastructure construction company operating mainly throughout North America across a range of industries. The Company’s primary activities include the engineering, building, installation, maintenance and upgrade of energy, utility and communications infrastructure, such as: petroleum and natural gas pipeline infrastructure; wireless, wireline and satellite communications; electrical utility transmission and distribution; power generation; and industrial infrastructure. MasTec’s customers are in these industries. MasTec reports its results in five reportable segments: (1) Communications; (2) Oil and Gas; (3) Electrical Transmission; (4) Power Generation and Industrial; and (5) Other. See Note 15 - Segments and Related Information.
	Basis of Presentation
	The accompanying condensed unaudited consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States (“U.S. GAAP”) for interim financial information and with the instructions for Form 10-Q and Rule 10-01 of Regulation S-X. Pursuant to these rules and regulations, certain information and footnote disclosures normally included in the annual consolidated financial statements prepared in accordance with U.S. GAAP have been condensed or omitted. The accompanying condensed consolidated balance sheet as of December 31, 2013 is derived from the Company’s audited financial statements as of that date. Because certain information and footnote disclosures have been condensed or omitted, these condensed unaudited consolidated financial statements should be read in conjunction with the audited consolidated financial statements and notes thereto as of and for the year ended December 31, 2013 contained in the Company’s most recent Annual Report on Form 10-K. In management’s opinion, all normal and recurring adjustments considered necessary for a fair presentation of the financial position, results of operations and cash flows for the periods presented have been included. Certain prior year amounts have been reclassified to conform to the current period presentation. Interim period operating results do not necessarily indicate the results that may be expected for any other interim period or for the full fiscal year. The Company believes that the disclosures made in these condensed unaudited consolidated financial statements are adequate to make the information not misleading.
	Principles of Consolidation
	The accompanying condensed unaudited consolidated financial statements include MasTec, Inc. and its subsidiaries and include the accounts of all majority owned subsidiaries over which the Company exercises control and, when applicable, entities in which the Company has a controlling financial interest. Other parties’ interests in companies for which MasTec exercises control and has a controlling financial interest are reported as non-controlling interests within equity. Net income or loss attributable to non-controlling interests is reported as a separate line item below net income. The Company’s investments in entities in which the Company does not have a controlling interest, but has the ability to exert significant influence, are accounted for using the equity method of accounting. Equity method investments are recorded as long-term assets in the condensed unaudited consolidated balance sheets. Income or loss from these investments is recorded in other income or expense, net, in the condensed unaudited consolidated statements of operations. The cost method is used for investments in entities in which the Company does not have the ability to exert significant influence. All significant intercompany balances and transactions have been eliminated in consolidation. The assets and liabilities of foreign subsidiaries are translated into U.S. dollars at period-end exchange rates, with resulting translation gains or losses accumulated within other comprehensive income or loss. Revenue and expenses are translated into U.S. dollars at average rates of exchange prevailing during the applicable period. Gains or losses resulting from transactions executed in a foreign currency are included in other income or expense, net. The Company does not currently have any subsidiaries that operate in highly inflationary environments. The results of operations and financial position of any discontinued operations are aggregated and presented separately from the Company's continuing operations in the condensed unaudited consolidated financial statements for all periods presented.
	Management Estimates
	The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. Key estimates include: the recognition of revenue, in particular, on long-term construction contracts, including estimates of costs to complete projects and provisions for contract losses; allowances for doubtful accounts; accrued self-insured claims; estimated fair values of goodwill and intangible assets, acquisition-related contingent consideration, assets and liabilities classified as held-for-sale, convertible debt obligations and investments in cost and equity method investees; asset lives used in computing depreciation and amortization, including amortization of intangible assets; share-based compensation; accounting for income taxes; and the estimated impact of contingencies and ongoing litigation. While management believes that such estimates are fair when considered in conjunction with the consolidated financial position and results of operations taken as a whole, actual results could differ from those estimates and such differences may be material to the condensed unaudited consolidated financial statements.
	Significant Accounting Policies
	Revenue Recognition
	Revenues are derived from projects performed under master and other service agreements as well as from fixed price contracts for specific projects or jobs requiring the construction and installation of an entire infrastructure system or specified units within an entire infrastructure system. Revenue and related costs for master and other service agreements billed on a time and materials basis are recognized as the services are rendered. The Company also performs services under master and other service agreements on a fixed fee basis, under which MasTec furnishes specified units of service for a fixed price per unit of service and revenue is recognized as the services are rendered. Revenues from fixed price contracts provide for a fixed amount of revenue for the entire project, subject to certain additions for changed scope or specifications. Revenues from these contracts are recognized using the percentage-of-completion method. Under this method, the percentage of revenue to be recognized for a given project is measured by the percentage of costs incurred to date on the contract to the total estimated costs for the contract. Such contracts provide that the customer accept completion of progress to date and compensate the Company for services rendered, which may be measured in terms of costs incurred, units installed, hours expended or some other measure of progress.
	The Company may incur costs subject to change orders, whether approved or unapproved by the customer, and/or claims related to certain contracts. Management determines the probability that such costs will be recovered based upon evidence such as engineering studies and legal opinions, past practices with the customer, specific discussions, correspondence or preliminary negotiations with the customer. The Company treats project costs as a cost of contract performance in the period incurred if it is not probable that the costs will be recovered, or defers costs and/or recognizes revenue up to the amount of the related cost if it is probable that the contract price will be adjusted and can be reliably estimated. As of March 31, 2014 and December 31, 2013, the Company had approximately $163 million and $79 million, respectively, of change orders and/or claims that had been included as contract price adjustments on certain contracts that were in the process of being negotiated in the normal course of business, including arbitration and other proceedings. These contract price adjustments represent management's best estimate of additional contract revenues that have been earned and that management believes are probable of collection. The amounts ultimately realized upon final acceptance by its customers could be higher or lower than such estimated amounts, which are primarily expected to be billed and collected within one year. The $84 million increase in change orders and/or claims since December 31, 2013 is primarily due to a project in our Oil and Gas segment, which amounts have been approved in principle subsequent to March 31, 2014.
	Except for adoption of the accounting pronouncement discussed below, there have been no material changes to the significant accounting policies described in the Company’s Annual Report on Form 10-K for the year ended December 31, 2013.
	New Accounting Pronouncements
	Accounting Standards Not Yet Adopted
	In April 2014, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2014-08, Presentation of Financial Statements (Topic 205) and Property, Plant, and Equipment (Topic 360): Reporting Discontinued Operations and Disclosures of Disposals of Components of an Entity (“ASU 2014-08”). ASU 2014-08 changes the requirements for reporting discontinued operations and requires additional disclosures about discontinued operations. Only disposals of components of an entity representing a strategic shift that has, or will have, a major effect on an entity’s operations and financial results should be reported as discontinued operations under ASU 2014-08. Examples include a disposal of a major geographical area, a major line of business, or a major equity method investment. ASU 2014-08 also requires expanded disclosures about discontinued operations and requires disclosures about individually significant dispositions that do not qualify as discontinued operations. ASU 2014-08 is effective prospectively for fiscal years, and interim periods within those years, beginning after December 15, 2014. Early adoption is permitted only for disposals that have not been previously reported. The Company is currently evaluating the potential impact of this ASU on its condensed unaudited consolidated financial statements.
	Recently Adopted Accounting Pronouncements
	In July 2013, the FASB issued ASU 2013-11, Income Taxes (Topic 740): Presentation of an Unrecognized Tax Benefit When a Net Operating Loss Carryforward, a Similar Tax Loss, or a Tax Credit Carryforward Exists (a consensus of the FASB Emerging Issues Task Force) (“ASU 2013-11”).  ASU 2013-11 provides guidance on the presentation in the financial statements of an unrecognized tax benefit, or a portion of an unrecognized tax benefit, and explains that unrecognized tax benefits should be presented as a reduction to deferred tax assets for net operating loss carryforwards, similar tax losses or tax credit carryforwards. To the extent a net operating loss carryforward, similar tax loss or tax credit carryforward is not available as of the reporting date under the tax law of the applicable jurisdiction, or the tax law of the applicable jurisdiction does not require the entity to use, and the entity does not intend to use, the deferred tax asset for such purpose, the unrecognized tax benefit should be presented in the financial statements as a liability and should not be combined with deferred tax assets. ASU 2013-11 applies to all entities that have unrecognized tax benefits when a net operating loss carryforward, similar tax loss, or tax credit carryforward exists as of the reporting date. ASU 2013-11 is effective prospectively for fiscal years, and interim periods within those years, beginning after December 15, 2013. Retrospective application is permitted. The Company adopted ASU 2013-11 as of January 1, 2014. The adoption of this ASU did not have a material impact on the condensed unaudited consolidated financial statements.

Earnings_Per_Share

Earnings Per Share	3 Months Ended
	Mar. 31, 2014
Earnings Per Share [Abstract]	'
Earnings Per Share	'
	Earnings Per Share
	Basic earnings per share is computed by dividing earnings available to MasTec’s common shareholders by the weighted average number of common shares outstanding for the period. Diluted earnings per share is computed by dividing earnings by the number of fully diluted shares, which includes the effect of dilutive potential issuances of common shares as determined using earnings from continuing operations. The potential issuance of common shares upon the exercise, conversion or vesting of outstanding stock options and unvested restricted share awards, as calculated under the treasury stock method, as well as shares associated with the Company’s outstanding convertible debt securities, may be dilutive.
	The following table provides details underlying the Company’s earnings per share calculations for the periods indicated (in thousands):
		For the Three Months Ended March 31,
		2014			2013
	Net income attributable to MasTec:
	Net income, continuing operations - basic (a)	$	16,145		$	19,317
	Interest expense, net of tax, 2009 Convertible Notes	78			77
	Net income, continuing operations - diluted	$	16,223		$	19,394
	Net loss from discontinued operations - basic and diluted (a)	(122		)	(947		)
	Net income attributable to MasTec - diluted	$	16,101		$	18,447
	Weighted average shares outstanding:
	Weighted average shares outstanding - basic	77,345			76,608
	Dilutive common stock equivalents	850			785
	Dilutive premium shares, 2011 Convertible Notes	7,621			5,895
	Dilutive shares, 2009 Convertible Notes	806			806
	Weighted average shares outstanding - diluted	86,622			84,094
	(a)	Calculated as total net income less amounts attributable to non-controlling interests.
	Outstanding Convertibles Notes - Diluted Share Impact
	The Company has $215 million aggregate principal amount of senior convertible notes outstanding, composed of $202.3 million of senior convertible notes issued in 2011 (the “2011 Convertible Notes”) and approximately $12.6 million of senior convertible notes issued in 2009 (the “2009 Convertible Notes”). Dilutive shares associated with the 2009 Convertible Notes are attributable to the underlying principal amounts. The number of common shares issuable upon conversion of the Company’s 2009 Convertible Notes is reflected in the calculation of weighted average diluted earnings per share for the corresponding periods by application of the “if-converted” method to the extent its effect on the computation of earnings per share from continuing operations is dilutive. Under the “if-converted” method, net income from continuing operations is adjusted to add back the after-tax amount of interest recognized for the period associated with the convertible notes, and correspondingly, the convertible notes are assumed to have been converted with the resulting common shares added to the number of weighted average shares outstanding. Due to the optional cash settlement feature of the 2011 Convertible Notes and the Company's intent to settle the principal amount of such notes in cash, the conversion shares underlying the outstanding principal amount of the 2011 Convertible Notes, totaling approximately 13.0 million shares, are not required to be included in the Company's diluted share count. If, however, the average price per share of the Company's common stock exceeds the respective conversion prices of the 2011 Convertible Notes, then the resulting premium is translated into shares, referred to as “premium shares,” the number of which is required to be included in the Company's diluted share count. The number of premium shares included in our diluted share count varies with fluctuations in our share price. Higher share prices result in a greater number of premium shares. The Company’s weighted average share price for the three month periods ended March 31, 2014 and 2013 exceeded the conversion prices of the 2011 Convertible Notes, and as a result, dilutive premium shares have been included in the Company's share count for the corresponding periods.
	The 2011 Convertible Notes consist of $105.3 million principal amount of 4.0% senior convertible notes, convertible at $15.76 per share (the “2011 4.0% Notes”), and $97.0 million principal amount of 4.25% senior convertible notes, convertible at $15.48 per share (the “2011 4.25% Notes”). The calculations underlying the number of premium shares included in the Company’s diluted share count for the periods indicated are as follows (in thousands, except per share amounts):
		As of and for the Three Months Ended March 31,
		2014						2013
	Premium Share Information:	2011 4.0%			2011 4.25%			2011 4.0%		2011 4.25%
		Notes			Notes			Notes		Notes
	Number of conversion shares, principal amount	6,683			6,268			6,683		6,268
	Weighted average actual per share price	$	37.96		$	37.96		$	28.68	$	28.68
	Weighted average premium value	$	148,360		$	140,925		$	86,316	$	82,735
	Weighted average equivalent premium shares	3,909			3,712			3,010		2,885
	Diluted Shares, Other Information
	For the three month period ended March 31, 2014, a total of 61,226 weighted average anti-dilutive common stock equivalents were not included in the Company's diluted earnings per share calculations. There were no anti-dilutive common stock equivalents for the three month period ended March 31, 2013.

Acquisitions

Acquisitions	3 Months Ended
	Mar. 31, 2014
Business Combinations [Abstract]	'
Acquisitions	'
	Acquisitions
	Allocations of purchase prices for acquisitions are based on estimates of the fair value of consideration paid and of the net assets acquired and are subject to adjustment upon finalization of these fair value estimates. The Company acquired several businesses during 2013 and 2014, as discussed below and in Note 3 - Acquisitions in the notes to the Company's consolidated financial statements included in its Annual Report on Form 10-K for the year ended December 31, 2013. As of March 31, 2014, the allocations of purchase price to the fair values of tangible and intangible assets and liabilities, including the estimated values of contingent earn-out obligations and the estimated useful lives of acquired assets for these acquisitions are provisional and remain preliminary. Management continues to assess the valuation of these items and any ultimate purchase price adjustments that may result based on the final net assets and net working capital of the acquired businesses, as prescribed in the corresponding purchase agreements.
	The Company will revise its preliminary allocations for acquired businesses if new information is obtained about the facts and circumstances existing as of the date of acquisition, or for purchase price adjustments based on the final net assets and net working capital of the acquired businesses, as prescribed in the applicable purchase agreement. Such adjustments result in the recognition of, or adjust the fair values of, acquired assets and assumed liabilities, which results in the revision of comparative prior period financial information. These measurement period adjustments are presented as if the adjustments had been taken into account as of the date of acquisition. All changes that do not qualify as measurement period adjustments are included in current period results. See table below pertaining to measurement period adjustments associated with the Company's 2013 acquisitions.
	2014 Acquisitions
	Effective January 1, 2014, MasTec acquired a telecommunications services firm that specializes in the engineering, installation, furnishing and integration of telecommunications equipment for an aggregate purchase price composed of approximately $23.8 million in cash and a five year earn-out, valued at $8.7 million as of the date of acquisition. This company is included in MasTec's Communications segment.
	2013 Acquisitions
	Big Country
	Effective May 1, 2013, MasTec acquired all of the issued and outstanding interests of Big Country Energy Services, Inc. and its affiliated operating companies (collectively, "Big Country"). Big Country is a North American oil and gas pipeline and facility construction services company, headquartered in Calgary, Alberta, Canada.
	Other 2013 Acquisitions
	Effective April 1, 2013, MasTec acquired a former subcontractor to its wireless business, which provides self-perform communications tower construction, installation, maintenance and other services in support of telecommunications infrastructure construction in the Company's Communications segment. In addition, effective August 1, 2013, MasTec acquired an electrical transmission services company, which focuses primarily on substation construction activities and is included within the Company's Electrical Transmission segment.
	Measurement Period Adjustments
	Measurement period adjustments associated with the Company's 2013 acquisitions have been reflected in the Company's December 31, 2013 consolidated balance sheet as follows (in millions):
	As of December 31, 2013		As Previously Reported			Measurement Period Adjustments		As Revised
	Current assets		$	1,306.00		$	0.2	$	1,306.20
	Goodwill		$	899.4		$	1.1	$	900.5
	Current liabilities		$	825.5		$	1.2	$	826.7
	Long-term deferred tax liabilities, net		$	154.9		$	0.1	$	155
	Unaudited Pro Forma Information
	The following unaudited supplemental pro forma financial information includes the results of operations of each of the companies acquired in 2014 and 2013 and is presented as if the acquired companies had been consolidated as of the beginning of the year immediately preceding the date of acquisition. The unaudited supplemental pro forma financial information has been provided for illustrative purposes only. The unaudited supplemental pro forma financial information does not purport to be indicative of the actual results that would have been achieved by the combined companies for the periods presented, or of the results that may be achieved by the combined companies in the future. Future results may vary significantly from the results reflected in the following unaudited supplemental pro forma financial information because of future events and transactions, as well as other factors, many of which are beyond MasTec’s control.
	The unaudited supplemental pro forma financial information presented below has been prepared by adjusting the historical results of MasTec to include the historical results of the acquired businesses described above. The unaudited supplemental pro forma combined historical results were then adjusted (i) to remove one-time acquisition costs; (ii) to increase amortization expense resulting from the incremental intangible assets acquired in such acquisitions; (iii) to increase interest expense as a result of the cash consideration paid; and (iv) to reduce interest expense from the repayment of acquired debt. The unaudited supplemental pro forma financial information does not include any adjustments to reflect the impact of cost savings or other synergies that may result from these acquisitions. As noted above, the unaudited supplemental pro forma financial information does not purport to be indicative of the actual results that would have been achieved by the combined companies for the periods presented or that may be achieved by the combined companies in the future.
		For the Three Months Ended March 31,
		2014			2013
	Pro forma financial information:	(unaudited, in millions)
	Revenue	$	964		$	1,029.10
	Net income from continuing operations	$	16.2		$	24.1
	Results of Businesses Acquired
	Revenues and net income resulting from the year over year incremental impact of acquired businesses, which are included within the Company's consolidated results of operations for the years indicated, are as follows (in millions):
		For the Three Months Ended March 31,
		2014			2013
	Year over year impact of acquired businesses:	(unaudited, in millions)
	Revenue	$	119.8		$	43.1
	Net income from continuing operations	$	1		$	1.8
	The above results do not include acquisition costs of $0.2 million and $0.4 million for the three month periods ended March 31, 2014 and March 31, 2013, respectively. The above results also do not include interest expense associated with consideration paid for these acquisitions.

Discontinued_Operations

Discontinued Operations	3 Months Ended
	Mar. 31, 2014
Discontinued Operations and Disposal Groups [Abstract]	'
Discontinued Operations	'
	Discontinued Operations
	Globetec
	In 2012, the Company's board of directors approved a plan of sale for its Globetec business. Accordingly, Globetec's projects and assets are reflected as assets and liabilities of discontinued operations in the condensed unaudited consolidated balance sheets for all periods presented, and Globetec's results of operations are presented as discontinued operations in the condensed unaudited consolidated statements of operations for all periods presented. Effective August 31, 2013, the Company sold all of its membership interests in Globetec for nominal consideration and retained certain contingent assets and liabilities. Additionally, the Company has $15.9 million of outstanding surety bonds associated with Globetec as of March 31, 2014 for projects that Globetec has either completed or expects to complete in 2014. The expected cost to complete these projects was estimated to be $0.5 million as of March 31, 2014. The Company believes that there was an insignificant amount at risk under these surety bonds as of March 31, 2014. The Company is not obligated and does not intend to support Globetec in the future.
	The following table contains a summary of the contingent assets and liabilities associated with Globetec that were retained by the Company as of March 31, 2014 and as of December 31, 2013 (in millions):
		March 31,			December 31,
		2014			2013
	Current assets	$	3.4		$	2.3
	Long-term assets	10.1			10.1
	Assets of discontinued operations	$	13.5		$	12.4
	Current liabilities of discontinued operations	$	1.3		$	1.2
	The following table presents results from discontinued operations associated with the Globetec operation for the periods indicated (in millions):
		For the Three Months Ended March 31, 2013
	Revenue	$	6.3
	Loss from operations, before tax	(1.2		)
	Benefit from income taxes	0.3
	Net loss from discontinued operations	$	(0.9	)

Goodwill_and_Other_Intangible_

Goodwill and Other Intangible Assets	3 Months Ended
	Mar. 31, 2014
Goodwill and Intangible Assets Disclosure [Abstract]	'
Goodwill and Other Intangible Assets	'
	Goodwill and Other Intangible Assets
	The following table provides a reconciliation of changes in goodwill by reportable segment (in millions):
		Communications			Oil and Gas				Electrical				Power				Total Goodwill
									Transmission				Generation and Industrial
	Balance as of December 31, 2013	$	327.9		$	305.2			$	149.8			$	117.6			$	900.5
	Additions from new business combinations	14.5			—				—				—				14.5
	Currency translation adjustments	—			(2.1		)		—				—				(2.1		)
	Balance as of March 31, 2014	$	342.4		$	303.1			$	149.8			$	117.6			$	912.9
	The following table provides a reconciliation of changes in other intangible assets (in millions):
			Other Intangible Assets
			Non-amortizing							Amortizing
			Trade Names			Pre-Qualifications				Customer Relationships and Backlog				Other (a)				Total
	Other intangible assets, gross carrying amount as of December 31, 2013		$	34.8		$	59.4			$	128.4			$	22.5			$	245.1
	Accumulated amortization									$	(67.7	)		$	(11.8	)		$	(79.5	)
	Other intangible assets, net, as of December 31, 2013		$	34.8		$	59.4			$	60.7			$	10.7			$	165.6
	Additions from new business combinations		—			—				11.7				0.3				12
	Amortization expense									(4.2		)		(0.4		)		(4.6		)
	Currency translation adjustments		—			(1.1		)		(0.2		)		(0.1		)		(1.4		)
	Other intangible assets, net, as of March 31, 2014		$	34.8		$	58.3			$	68			$	10.5			$	171.6
	(a) Consists principally of trade names and non-compete agreements.
	Amortization expense associated with intangible assets for the three month periods ended March 31, 2014 and 2013 totaled $4.6 million and $4.2 million, respectively.

Fair_Value_of_Financial_Instru

Fair Value of Financial Instruments	3 Months Ended
	Mar. 31, 2014
Fair Value Disclosures [Abstract]	'
Fair Value of Financial Instruments	'
	Fair Value of Financial Instruments
	The Company’s financial instruments include cash and cash equivalents, accounts and notes receivable, cash collateral deposited with insurance carriers, life insurance assets, cost and equity method investments, deferred compensation plan assets and liabilities, accounts payable and other current liabilities, acquisition-related contingent consideration and debt obligations.
	Fair value is the price that would be received to sell an asset or paid to transfer a liability (an exit price) in the principal or most advantageous market for the asset or liability in an orderly transaction between market participants on the measurement date. The fair value guidance establishes a valuation hierarchy, which requires maximizing the use of observable inputs when measuring fair value. The three levels of inputs that may be used are:
	Level 1 - Quoted market prices in active markets for identical assets or liabilities.
	Level 2 - Observable market based inputs or other observable inputs.
	Level 3 - Significant unobservable inputs that cannot be corroborated by observable market data. These values are generally determined using valuation models incorporating management’s estimates of market participant assumptions.
	Assets and Liabilities Measured at Fair Value on a Recurring Basis
	As of March 31, 2014, the Company held certain assets and liabilities required to be measured at fair value on a recurring basis. The fair value hierarchy requires the use of observable market data when available. In instances in which the inputs used to measure fair value fall into different levels of the fair value hierarchy, the fair value measurement classification below has been determined based on the lowest level input that is significant to the fair value measurement in its entirety.  Management’s assessment of the significance of a particular item to the fair value measurement in its entirety requires judgment, including the consideration of inputs specific to the asset or liability.  The fair values of financial assets and liabilities measured on a recurring basis were determined using the following inputs as of the dates indicated (in millions):
				Fair Value Measurements
				Using Inputs Considered as Significant
		Fair Value as of		Level 1		Level 2		Level 3
		31-Mar-14
	Assets
	Life insurance surrender values	$	5.5	$	5.5
	Liabilities
	Acquisition-related contingent consideration	$	170.3					$	170.3
				Fair Value Measurements
				Using Inputs Considered as Significant
		Fair Value as of		Level 1		Level 2		Level 3
		31-Dec-13
	Assets
	Life insurance surrender values	$	5.3	$	5.3
	Liabilities
	Acquisition-related contingent consideration	$	162.9					$	162.9
	Life Insurance Surrender Values. Cash surrender values of life insurance policies are based on current cash surrender values as quoted by insurance carriers. Life insurance policies support the Company’s deferred compensation plan assets and certain of its split dollar agreements.
	Acquisition-Related Contingent Consideration. Acquisition-related contingent consideration presented in the table above represents the estimated fair value of additional future earn-outs payable for acquisitions of businesses that closed after January 1, 2009, in accordance with U.S. GAAP. The fair value of such acquisition-related contingent consideration is based on management’s estimates and entity-specific assumptions and is evaluated on an on-going basis. Additions to acquisition-related contingent consideration totaled $8.7 million for the three month period ended March 31, 2014. There were no additions for the three month period ended March 31, 2013. The Company made no payments in connection with acquisition-related contingent consideration obligations measured at fair value on a recurring basis for the three months ended March 31, 2014. The Company paid approximately $0.6 million for the three month period ended March 31, 2013. Foreign currency translation gains included in other comprehensive income totaled $1.4 million and $0.4 million for the three month periods ended March 31, 2014 and 2013, respectively.
	Assets and Liabilities Measured at Fair Value on a Non-Recurring Basis
	Assets and liabilities recognized or disclosed at fair value on a non-recurring basis, which are initially measured at fair value, and are subsequently remeasured in the event of an impairment or other measurement event, if applicable, include items such as cost and equity method investments, goodwill, other intangible assets, long-lived assets and debt.
	Carrying amounts and estimated fair values of selected financial instruments measured on a non-recurring basis as of the dates indicated were as follows (in millions):
		March 31, 2014				December 31, 2013
		Carrying		Fair		Carrying				Fair
		Amount		Value		Amount				Value
	4.875% Senior Notes	$	400	$	390.5	$	400			$	380
	2009 Convertible Notes	$	12.6	$	35	$	12.6			$	26.6
	2011 Convertible Notes	$	199.7	$	563.2	$	198.3			$	428.3
	The estimated fair values of the Company’s 4.875% Senior Notes, 2009 Convertible Notes and 2011 Convertible Notes are based on quoted market prices, a Level 1 input.

Accounts_Receivable_Net_of_All

Accounts Receivable, Net of Allowance	3 Months Ended
	Mar. 31, 2014
Receivables [Abstract]	'
Accounts Receivable, Net of Allowance	'
	Accounts Receivable, Net of Allowance
	The following table provides details of accounts receivable, net of allowance, as of the dates indicated (in millions):
		March 31,			December 31,
		2014			2013
	Contract billings	$	627.1		$	606.5
	Retainage	135.6			159.3
	Costs and earnings in excess of billings	448.6			384.6
	Accounts receivable, gross	$	1,211.30		$	1,150.40
	Less allowance for doubtful accounts	(15.7		)	(15.8		)
	Accounts receivable, net	$	1,195.60		$	1,134.60
	Provisions for doubtful accounts were $0.6 million and $3.3 million, respectively, for the three month periods ended March 31, 2014 and March 31, 2013.

Debt

Debt	3 Months Ended
	Mar. 31, 2014
Debt Disclosure [Abstract]	'
Debt	'
	Debt
	The following table provides details of the carrying values of debt as of the dates indicated (in millions):
	Description		Maturity Date	March 31,				December 31,
				2014				2013
	Credit facility		October 29, 2018	$	128.6			$	53
	4.875% senior notes		March 15, 2023	400				400
	2011 4.0% senior convertible notes		June 15, 2014	104.6				103.8
	2011 4.25% senior convertible notes		December 15, 2014	95.1				94.5
	2009 4.0% senior convertible notes		June 15, 2014	9.6				9.6
	2009 4.25% senior convertible notes		December 15, 2014	3				3
	Capital lease obligations, weighted average interest rate of 2.9%		In installments through March 30, 2020	123.2				126
	Notes payable for equipment, weighted average interest rate of 3.0%		In installments through May 1, 2018	30.1				26.9
	Total debt			$	894.2			$	816.8
	Less current maturities			(52.9		)		(51.4		)
	Long-term debt			$	841.3			$	765.4
	Credit Facility
	The Company has a senior secured credit facility, referred to as the 2013 Credit Facility. The 2013 Credit Facility matures on October 29, 2018 and has a maximum available borrowing capacity of $750 million, of which up to $100 million may be borrowed in Canadian dollars. As of March 31, 2014 and December 31, 2013, the Company had outstanding revolving loans under the 2013 Credit Facility of $128.6 million and $53.0 million, respectively, which accrued interest at a weighted average rate of approximately 2.08% and 2.14% per annum, respectively. Letters of credit of approximately $134.7 million and $134.8 million were outstanding as of March 31, 2014 and December 31, 2013, respectively. The remaining borrowing capacity of $486.8 million and $562.1 million as of March 31, 2014 and December 31, 2013, respectively, was available for revolving loans, or up to $315.3 million and $315.2 million, respectively, of new letters of credit. Outstanding letters of credit mature at various dates and most have automatic renewal provisions, subject to prior notice of cancellation. As of March 31, 2014 and December 31, 2013, interest on outstanding letters of credit accrued at 0.75% per annum for performance standby letters of credit and at 1.50% per annum for financial standby letters of credit. The unused facility fee was 0.30% as of both March 31, 2014 and December 31, 2013. The 2013 Credit Facility is guaranteed by certain subsidiaries of the Company.
	For additional information regarding the Company's 2013 Credit Facility see Note 9 - Debt in the notes to the Company's consolidated financial statements included in its Annual Report on Form 10-K for the year ended December 31, 2013.
	Senior Convertible Notes
	Unamortized debt discount and financing costs associated with the Company's 2011 Convertible Notes totaled $2.7 million and $4.0 million as of March 31, 2014 and December 31, 2013, respectively. The 4.0% senior convertible notes mature in June 2014 and the 4.25% senior convertible notes mature in December 2014. The Company expects to refinance the $215.0 million principal amount of its senior convertible notes on a long-term basis either through its 2013 Credit Facility or through other sources of available funding and, therefore, has reflected the carrying amounts of these notes within long-term debt in the Company's condensed unaudited consolidated balance sheets.
	For additional information regarding the Company's senior convertible notes, see Note 9 - Debt in the notes to the Company's consolidated financial statements included in its Annual Report on Form 10-K for the year ended December 31, 2013.
	Debt Guarantees and Covenants
	The Company’s 4.875% Senior Notes, 2011 Convertible Notes and 2009 Convertible Notes are fully and unconditionally guaranteed on an unsecured, unsubordinated, joint and several basis by certain of the Company's existing and future 100%-owned direct and indirect domestic subsidiaries that are guarantors of the 2013 Credit Facility or other outstanding indebtedness. See Note 18 - Supplemental Guarantor Condensed Unaudited Consolidating Financial Information.
	MasTec was in compliance with all provisions and covenants pertaining to its outstanding debt instruments as of March 31, 2014 and December 31, 2013.
	Interest Expense, Net
	The following table provides details of interest expense, net, for the periods indicated (in millions):
		For the Three Months Ended March 31,
		2014			2013
	Interest expense:
	Contractual and other interest expense	$	9.7		$	7.9
	Accretion of senior convertible note discount	1.4			1.3
	Amortization of deferred financing costs	0.9			0.9
	Total interest expense	$	12		$	10.1
	Interest income	0			(0.1		)
	Interest expense, net	$	12		$	10

Property_and_Equipment_Net

Property and Equipment, Net	3 Months Ended
	Mar. 31, 2014
Property, Plant and Equipment [Abstract]	'
Property and Equipment, Net	'
	Property and Equipment, Net
	The following table provides details of property and equipment, net, including property and equipment held under capital leases as of the dates indicated (in millions):
		March 31,			December 31,
		2014			2013
	Land	$	4.6		$	4.8
	Buildings and leasehold improvements	17.6			18
	Machinery and equipment	752.2			727.1
	Office furniture and equipment	108			102.5
	Construction in progress	16.9			11
	Total property and equipment	$	899.3		$	863.4
	Less accumulated depreciation and amortization	(389.7		)	(375.3		)
	Property and equipment, net	$	509.6		$	488.1
	Depreciation and amortization expense associated with property and equipment for the three month periods ended March 31, 2014 and 2013 totaled $28.9 million and $27.6 million, respectively.

Lease_Obligations

Lease Obligations	3 Months Ended
	Mar. 31, 2014
Leases [Abstract]	'
Lease Obligations	'
	Lease Obligations
	Capital Leases
	MasTec enters into agreements that provide financing for machinery and equipment, which expire on various dates. The gross amount of assets held under capital leases as of March 31, 2014 and December 31, 2013 totaled $207.8 million and $199.6 million, respectively. Assets held under capital leases, net of accumulated depreciation, totaled $144.1 million and $141.3 million as of March 31, 2014 and December 31, 2013, respectively.
	Operating Leases
	In the ordinary course of business, the Company enters into non-cancelable operating leases for certain of its facility, vehicle and equipment needs, including related party leases. Rent expense relating to operating leases that have non-cancelable terms in excess of one year was approximately $15.5 million and $11.9 million for the three month periods ended March 31, 2014 and 2013, respectively. The Company also incurred expenses relating to facilities, vehicles and equipment having original terms of one year or less of approximately $48.4 million and $36.9 million for the three month periods ended March 31, 2014 and 2013, respectively.

StockBased_Compensation_and_Ot

Stock-Based Compensation and Other Employee Benefit Plans	3 Months Ended
	Mar. 31, 2014
Share-based Compensation [Abstract]	'
Stock-Based Compensation and Other Employee Benefit Plans	'
	Stock-Based Compensation and Other Employee Benefit Plans
	The Company has certain stock-based compensation plans, under which stock options and restricted share awards are available for issuance or outstanding. Under stock-based compensation plans in effect as of March 31, 2014, there were a total of 6,243,047 shares available for grant or issuance.
	Restricted Share Awards
	MasTec grants restricted share awards, which are valued based on the market price of MasTec common stock on the date of grant. Total unearned compensation related to restricted share awards as of March 31, 2014 was approximately $24.3 million, which is expected to be recognized over a weighted average period of approximately 1.6 years. The total intrinsic value, or fair value, of restricted share awards that vested, which is based on the market price on the date of vesting, was $5.9 million and $0.7 million for the three month periods ended March 31, 2014 and 2013.
	Activity, restricted share awards:	Restricted		Weighted Average Grant Date
		Shares		Fair Value
	Non-vested restricted shares, as of December 31, 2013	1,123,545		$	23.78
	Granted	326,442		41.39
	Vested	(141,138	)	19.41
	Canceled/forfeited	(13,450	)	16.05
	Non-vested restricted shares, as of March 31, 2014	1,295,399		$	28.77
	Stock Options
	The Company has granted options to purchase its common stock to employees and members of the Board of Directors and affiliates under various stock option plans at not less than the fair market value of the underlying stock on the date of grant. All outstanding stock options are fully vested.
	Activity, stock options:	Stock		Per Share Weighted Average			Weighted Average	Aggregate Intrinsic
		Options		Exercise Price			Remaining	Value (a)
							Contractual Life (in years)	(in millions)
	Options outstanding as of December 31, 2013	495,571		$	11.17		1.96	$	10.7
	Exercised	(200,900	)	9.77
	Canceled/forfeited	—		—
	Options outstanding as of March 31, 2014	294,671		$	12.13		2.04	$	9.2
	Options exercisable as of March 31, 2014	294,671		$	12.13		2.04	$	9.2
	(a)	Amount represents the difference between the exercise price and the market price of the Company’s stock on the last trading day of the corresponding period, multiplied by the number of in-the-money options.
	The total intrinsic value of options exercised during the three month periods ended March 31, 2014 and 2013, which is based on the difference between the exercise price and the market price of the Company’s stock at the date of exercise, was $6.3 million and $3.5 million, respectively. Proceeds from options exercised during the three month periods ended March 31, 2014 and 2013 totaled $0.6 million and $1.9 million, respectively.
	Employee Stock Purchase Plans
	The Company's employee stock purchase plans allow qualified employees to purchase MasTec, Inc. common stock at 85% of the fair market value of the common stock at the lower of (i) the date of commencement of the offering period or (ii) the last day of the exercise period, as defined in the plan documents. The fair value of purchases under the Company's employee stock purchase plans is estimated using the Black-Scholes option-pricing valuation model.
		Three Months Ended March 31,
	Activity, employee stock purchase plan:	2014			2013
	Cash proceeds (in millions)	$	0.8		$	0.9
	Common shares issued	26,968			67,556
	Weighted average price per share	$	27.81		$	13.19
	Weighted average grant date fair value per share	$	6.59		$	5
	Stock-Based Compensation Expense and Tax Benefits
	Details of stock based compensation expense, which is included within general and administrative expense in the condensed unaudited consolidated statement of operations, and related tax benefits for the periods indicated are as follows (in millions):
		Three Months Ended March 31,
		2014			2013
	Stock-based compensation expense	$	3.3		$	2.4
	Income Tax Effects:
	Income tax benefit from stock-based compensation	$	4.5		$	1.5
	Excess tax benefit from stock-based compensation (a)	$	3.2		$	0.9
	(a)	Excess tax benefits, which represent cash flows from tax deductions in excess of the recorded tax effect of compensation expense recognized for stock options exercised and vested restricted shares, are classified as financing cash flows in the Company’s condensed unaudited consolidated statements of cash flows.

Other_Retirement_Plans

Other Retirement Plans	3 Months Ended
	Mar. 31, 2014
Multiemployer Plans [Abstract]	'
Other Retirement Plans	'
	Other Retirement Plans
	Multi-Employer Plans. Certain of MasTec’s subsidiaries contribute amounts to multi-employer pension and other multi-employer benefit plans and trusts. Contributions are generally based on fixed amounts per hour per employee for employees covered under these plans. Multi-employer plan contribution rates are determined annually and assessed on a “pay-as-you-go” basis based on union employee payrolls. Union payrolls cannot be determined for future periods because the number of union employees employed at any given time, and the plans in which they may participate, vary depending upon the location and number of ongoing projects at a given time and the need for union resources in connection with those projects. Total contributions to multi-employer plans, and the related number of employees covered by these plans, for the periods indicated ranged as follows:
		Multi-Employer Plans
		Covered Employees		Contributions (in millions)
	For the Three Months Ended March 31,	Low	High	Pension		Post-Retirement Benefit		Total
	2014	1,098	1,308	$	7.8	$	0.5	$	8.3
	2013	778	1,149	$	8.3	$	0.8	$	9.1

Equity

Equity	3 Months Ended
	Mar. 31, 2014
Equity [Abstract]	'
Equity	'
	Equity
	The following is a summary of share activity for the period indicated:
	Share Activity (in thousands):	Common Shares			Treasury
		Outstanding			Shares
	Balance as of December 31, 2013	77,258			9,467
	Shares issued for stock option exercises	201
	Shares issued for restricted stock awards	141
	Other shares issued, net of shares withheld for taxes	(73	)
	Balance as of March 31, 2014	77,527			9,467
	Accumulated Other Comprehensive Loss
	Changes in accumulated other comprehensive loss by component during the periods indicated are as follows (in thousands):
			For the Three Months Ended March 31,
			2014									2013
			Unrealized (Losses) Gains
			Foreign Currency			Available-for-Sale Securities			Total			Foreign Currency			Available-for-Sale Securities			Total
	Balance as of January 1		$	(7,998	)	$	(5,288	)	$	(13,286	)	$	(105	)	$	(5,396	)	$	(5,501	)
	Activity before reclassifications, net of tax		(5,335		)	—			(5,335		)	(824		)	221			(603		)
	Reclassifications, net of tax		—			—			—			—			—			—
	Activity, net of tax		(5,335		)	—			(5,335		)	(824		)	221			(603		)
	Balance as of March 31		$	(13,333	)	$	(5,288	)	$	(18,621	)	$	(929	)	$	(5,175	)	$	(6,104	)
	Foreign currency activity is primarily related to the Company's Canadian operations. The Company's Canadian presence has grown in recent years due to acquisitions. See Note 3 - Acquisitions.

Income_Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2014
Income Tax Disclosure [Abstract]	'
Income Taxes	'
	Income Taxes
	The Company’s consolidated tax rates on income from continuing operations for the three month periods ended March 31, 2014 and 2013 were 38.0% and 39.0%, respectively. In determining the quarterly provision for income taxes, management uses an estimated annual effective tax rate based on forecasted annual pre-tax income, permanent tax differences, statutory tax rates and tax planning opportunities in the various jurisdictions in which the Company operates. The impact of significant discrete items is separately recognized in the quarter(s) in which they occur.
	As of March 31, 2014, the Company had $12.7 million of current deferred tax assets, net, and $154.2 million of long-term deferred tax liabilities, net. As of December 31, 2013, current deferred tax assets, net, totaled $16.3 million and long-term deferred tax liabilities, net, totaled $155.0 million.

Segments_and_Related_Informati

Segments and Related Information	3 Months Ended
	Mar. 31, 2014
Segment Reporting [Abstract]	'
Segments and Related Information	'
	Segments and Related Information
	Segment Discussion
	MasTec presents its continuing operations in five reportable segments: (1) Communications; (2) Oil and Gas; (3) Electrical Transmission; (4) Power Generation and Industrial and (5) Other. This structure is generally focused on broad end-user markets for MasTec's labor-based construction services. All five reportable segments derive their revenues from the engineering, installation and maintenance of infrastructure, primarily in North America.
	The Communications segment performs engineering, construction and maintenance of communications infrastructure primarily related to wireless and wireline communications and install to the home, and to a lesser extent, infrastructure for electrical utilities. MasTec performs engineering, construction and maintenance services on oil and natural gas pipelines and processing facilities for the energy and utilities industries through its Oil and Gas segment. The Electrical Transmission segment primarily serves the energy and utility industries through the engineering, construction and maintenance of electrical transmission lines and substations. The Power Generation and Industrial segment primarily serves the energy and utility end markets and other end markets through the installation and construction of renewable power facilities, related electrical transmission infrastructure, ethanol facilities and various types of industrial infrastructure. The Other segment primarily includes small business units that perform construction services for a variety of end markets in Mexico and elsewhere internationally.
	Earnings before interest, taxes, depreciation and amortization (“EBITDA”) is the measure of profitability used by management to manage its segments and, accordingly, in its segment reporting. As appropriate, the Company supplements the reporting of consolidated financial information determined in accordance with U.S. GAAP with certain non-U.S. GAAP financial measures, including EBITDA. The Company believes these non-U.S. GAAP measures provide meaningful information that helps investors understand the Company's financial results and assess its prospects for future performance. The Company uses EBITDA to evaluate its performance, both internally and versus that of its peers, because it excludes certain items that may not be indicative of the Company's reportable segment results, as well as items that can vary widely across different industries or among companies within the same industry. Segment EBITDA is calculated in a manner consistent with consolidated EBITDA.
	Summarized financial information for MasTec’s reportable segments is presented and reconciled to consolidated continuing operations financial information for total MasTec in the following tables (in millions):
		For the Three Months Ended March 31,
	Revenue:	2014			2013
	Communications	$	447.1		$	424.9
	Oil and Gas	379.8			318.8
	Electrical Transmission	80.1			84.6
	Power Generation and Industrial	54.2			88.9
	Other	2.8			2.3
	Eliminations	0			(0.9		)
	Consolidated revenue	$	964		$	918.6
	Revenue generated by utilities customers represented 7.0% and 8.3% of Communications segment revenue for the three month periods ended March 31, 2014 and 2013, respectively.
		For the Three Months Ended March 31,
	EBITDA:	2014			2013
	Communications	$	43.4		$	46.4
	Oil and Gas	34.9			42.4
	Electrical Transmission	3.5			3.4
	Power Generation and Industrial	0.5			(0.2		)
	Other	0.2			0.1
	Corporate	(10.9		)	(18.6		)
	Consolidated EBITDA	$	71.6		$	73.5
		For the Three Months Ended March 31,
	Depreciation and Amortization:	2014			2013
	Communications	$	9.9		$	8.2
	Oil and Gas	18.1			18.7
	Electrical Transmission	2.8			2.3
	Power Generation and Industrial	1.5			1.7
	Corporate	1.2			0.9
	Consolidated Depreciation and Amortization	$	33.5		$	31.8
	The following table presents a reconciliation of EBITDA to consolidated income from continuing operations before income taxes (in millions):
		For the Three Months Ended March 31,
	EBITDA Reconciliation:	2014			2013
	EBITDA	$	71.6		$	73.5
	Less:
	Interest expense, net	(12.0		)	(10.0		)
	Depreciation and amortization	(33.5		)	(31.8		)
	Income from continuing operations before income taxes	$	26.1		$	31.7
	Foreign Operations. MasTec operates throughout North America, primarily in the United States and Canada, as well as in parts of Latin America. For the three months ended March 31, 2014 and 2013, revenues of $837.9 million and $878.9 million, respectively, were derived in the United States, and $126.1 million and $39.7 million, respectively, were derived from foreign operations. Long-lived assets held in the United States include property and equipment, net, of $461.8 million and $436.9 million as of March 31, 2014 and December 31, 2013, respectively. Long-lived assets held in foreign countries, primarily in Canada, include property and equipment, net, of $47.8 million and $51.2 million as of March 31, 2014 and December 31, 2013, respectively. Intangible assets and goodwill, net of $995.8 million and $973.3 million as of March 31, 2014 and December 31, 2013, respectively, relate to businesses in the United States. Intangible assets and goodwill, net, of $88.6 million and $92.7 million as of March 31, 2014 and December 31, 2013, respectively, relate to businesses in foreign countries.
	Significant Customers
	Revenue concentration information for significant customers as a percent of total consolidated revenue was as follows:
		For the Three Months Ended March 31,
		2014		2013
	Customer:
	AT&T	22%		18%
	DIRECTV®	14%		16%
	Enbridge, Inc.	14%		12%
	The Company's relationship with AT&T is based upon master service agreements, other service agreements and construction/installation contracts for AT&T's wireless, wireline and home security and automation businesses. Revenue from AT&T is included in the Communications segment. The Company's relationship with DIRECTV® is based upon an agreement to provide installation and maintenance services for DIRECTV®. Revenue from DIRECTV® is included in the Communications segment. The Company's relationship with Enbridge, Inc. is based upon various construction contracts for natural gas pipelines. Revenue from Enbridge, Inc. is included in the Oil and Gas segment.

Commitments_and_Contingencies

Commitments and Contingencies	3 Months Ended
	Mar. 31, 2014
Commitments and Contingencies Disclosure [Abstract]	'
Commitments and Contingencies	'
	Commitments and Contingencies
	In addition to the matters discussed below, MasTec is subject to a variety of legal cases, claims and other disputes that arise from time to time in the ordinary course of its business. MasTec cannot provide assurance that it will be successful in recovering all or any of the potential damages it has claimed or in defending claims against it. The outcome of such cases, claims and disputes (including the one set forth below) cannot be predicted with certainty and an unfavorable resolution of one or more of them could have a material adverse effect on the Company's business, financial condition, results of operations, cash flows and the trading price of its common stock.
	SunLight Entities. In 2011, Power Partners MasTec, LLC., a MasTec, Inc. subsidiary (“Power Partners”), entered into engineering, procurement, and construction agreements with special purpose entities, SunLight General Somerset Solar, LLC, SunLight General Morris Solar, LLC and SunLight General Sussex Solar, LLC (collectively, the “SunLight Entities”), respectively, to perform design and construction services for three public solar projects in New Jersey located in Somerset, Morris and Sussex Counties (the “Projects”). The initial contract price of each of the Projects was, subject to adjustment, approximately as follows: Somerset ($29 million); Morris ($36 million); and Sussex ($26 million). The Projects were funded on a project finance basis, including the proceeds of municipal bonds issued by the Morris County and Somerset Improvement Authorities (collectively, the “Authorities”).
	Power Partners and the SunLight Entities commenced three separate arbitration proceedings against each other to address various disputes that presently exist between the parties on the three Projects. The parties allege, among other things, breach of contract against each other. The arbitrations began in January 2014 and an award is anticipated in the summer of 2014. Power Partners believes it has presented meritorious support of its claims against Sunlight and, additionally, believes that it has meritorious defenses against Sunlight’s claims. Power Partners is vigorously pursuing its claims against Sunlight and vigorously defending against Sunlight’s claims.
	Power Partners filed municipal liens and construction liens of approximately $50 million for the work performed but the liens were challenged by the SunLight Entities and the Authorities. On March 24, 2014, the New Jersey appellate court found that Power Partners did not have municipal or construction liens on the proceeds of the municipal bonds. The New Jersey Supreme Court denied Power Partner’s emergency motion to stay the adverse ruling. The Company is currently petitioning the New Jersey Supreme Court to review the New Jersey appellate court’s adverse ruling.
	Power Partners also filed a federal lawsuit in the United States District Court of New Jersey against the Authorities and the principals of the SunLight Entities in June 2013. The claims against the Authorities include violations of the New Jersey Public Works Bond Act and the New Jersey Construction Trust Fund Act, tortious interference and unjust enrichment and quantum meruit. The Authorities and the SunLight principals have filed motions to dismiss. Power Partners has filed a response to the motions to dismiss. The litigation is in the early stages.
	Other Commitments and Contingencies
	Leases. In the ordinary course of business, the Company enters into non-cancelable operating leases for certain of its facility, vehicle and equipment needs, including related party leases. See Note 10 - Lease Obligations.
	Letters of Credit. In the ordinary course of business, the Company is required to post letters of credit for its insurance carriers, surety bond providers and in support of performance under certain contracts. Such letters of credit are generally issued by a bank or similar financial institution. The letter of credit commits the issuer to pay specified amounts to the holder of the letter of credit under certain conditions. If this were to occur, the Company would be required to reimburse the issuer of the letter of credit, which, depending upon the circumstances, could result in a charge to earnings. As of March 31, 2014 and December 31, 2013, the Company had $134.7 million and $134.8 million, respectively, of letters of credit issued under its 2013 Credit Facility. The Company was not aware of any material claims relating to outstanding letters of credit as of March 31, 2014 or December 31, 2013.
	Performance and Payment Bonds. In the ordinary course of business, MasTec is required by certain customers to provide performance and payment bonds for some of the Company’s contractual commitments related to projects in process. These bonds provide a guarantee to the customer that the Company will perform under the terms of a contract and that the Company will pay subcontractors and vendors. If the Company fails to perform under a contract or to pay subcontractors and vendors, the customer may demand that the surety make payments or provide services under the bond. The Company must reimburse the surety for any expenses or outlays it incurs. As of March 31, 2014, the estimated cost to complete projects secured by the Company’s $1.0 billion in performance and payment bonds was $281.6 million. As of December 31, 2013, the estimated cost to complete projects secured by the Company’s $1.1 billion in performance and payment bonds was $297.1 million.
	Self-Insurance. MasTec maintains insurance policies for workers’ compensation, general liability and automobile liability, which are subject to per claim deductibles. The Company also maintains excess umbrella coverage. As of March 31, 2014 and December 31, 2013, MasTec’s liability for unpaid claims and associated expenses, including incurred but not reported losses related to its workers compensation, general liability and automobile liability insurance policies, was $50.9 million and $50.8 million, respectively, of which $32.0 million and $31.3 million, respectively, was reflected within non-current other liabilities in the condensed unaudited consolidated balance sheets. MasTec also maintains an insurance policy with respect to employee group medical claims, which is subject to annual per employee maximum losses. MasTec’s liability for employee group medical claims as of March 31, 2014 and December 31, 2013 was $1.9 million and $2.1 million, respectively.
	The Company is required to post letters of credit and provide cash collateral to certain of its insurance carriers and to provide surety bonds in certain states. These letters of credit amounted to $57.4 million as of both March 31, 2014 and December 31, 2013. In addition, cash collateral deposited with insurance carriers, which is included in other long-term assets in the condensed unaudited consolidated balance sheets, amounted to $1.4 million as of both March 31, 2014 and December 31, 2013. Outstanding surety bonds related to workers’ compensation self-insurance programs amounted to $10.9 million as of both March 31, 2014 and December 31, 2013.
	Employment Agreements. The Company has employment agreements with certain executives and other employees, which provide for compensation and certain other benefits and for severance payments under certain circumstances. Certain employment agreements also contain clauses that become effective upon a change of control of the Company. Upon the occurrence of any of the defined events in the various employment agreements, the Company would be obligated to pay certain amounts to the relevant employees, which vary with the level of the employees’ respective responsibility.
	Collective Bargaining Agreements and Multi-Employer Plans. Certain of MasTec’s subsidiaries are party to various collective bargaining agreements with unions representing certain of their employees. The agreements require the subsidiaries party to the agreements to pay specified wages, provide certain benefits to their union employees and contribute certain amounts to multi-employer pension plans and employee benefit trusts. The collective bargaining agreements expire at various times and have typically been renegotiated and renewed on terms similar to the ones contained in the expiring agreements.
	The Employee Retirement Income Security Act of 1974, as amended by the Multi-Employer Pension Plan Amendments Act of 1980 (collectively, “ERISA”), subjects employers to substantial liabilities in the event of the employer’s complete or partial withdrawal from, or upon termination of, such plans. Under current law regarding employers who are contributors to multi-employer defined benefit plans, a plan’s termination, an employer’s voluntary withdrawal from, or the mass withdrawal of all contributing employers from, an underfunded multi-employer defined benefit plan requires participating employers to make payments to the plan for their proportionate share of the multi-employer plan’s unfunded vested liabilities. Furthermore, the Pension Protection Act of 2006 added new funding rules generally applicable to plan years beginning after 2007 for multi-employer plans that are classified as “endangered,” “seriously endangered,” or “critical” status. If plans in which the Company’s subsidiaries participate are in critical status, benefit reductions may apply and/or the Company could be required to make additional contributions if the plans are determined to be underfunded. Based upon the information available to the Company from plan administrators as of March 31, 2014, several of the multi-employer pension plans in which the Company’s subsidiaries participate are underfunded and the Company could be required to increase its contributions to such plans.
	On November 15, 2011, the Company, along with other members of the Pipe Line Contractors Association (“PLCA”), voluntarily withdrew from the Central States Southeast and Southwest Areas Pension Fund (“Central States”), a defined benefit multi-employer pension plan that is in critical status. In connection with this withdrawal, a $6.4 million withdrawal liability was established based on an estimate provided by the Central States administrator of such liability as of the date of withdrawal. The Company began paying installments towards this withdrawal liability in 2013, of which $5.1 million was outstanding as of March 31, 2014. The Company withdrew from Central States in order to mitigate its liability in connection with the plan; however, Central States has asserted that the PLCA members did not effectively withdraw in 2011 and are, therefore, responsible for a withdrawal liability that includes 2011 contribution amounts. By letter dated March 14, 2013, Central States demanded $11 million in withdrawal liability from the Company, which included 2011 contribution amounts. The Company is vigorously opposing this demand because it believes that it legally and effectively withdrew from Central States on November 15, 2011. If Central States were to prevail in its assertion that the Company withdrew after that date, then the initial amount of the Company’s withdrawal liability would increase to approximately $11 million. In addition, if Central States were to undergo a mass withdrawal, as defined by ERISA and the Pension Benefit Guaranty Corporation, within the three year period commencing with the beginning of the calendar year during which the Company withdrew from the plan, there could be additional liability. The Company currently does not have plans to withdraw from any other multi-employer pension plan.
	Indemnities. The Company generally indemnifies its customers for the services it provides under its contracts, as well as other specified liabilities, which may subject the Company to indemnity claims, liabilities and related litigation. As of March 31, 2014 and December 31, 2013, the Company was not aware of any material asserted or unasserted claims in connection with these indemnity obligations.
	Other Guarantees. In the ordinary course of its business, from time to time, MasTec guarantees the obligations of its subsidiaries, including obligations under certain contracts with customers, certain lease obligations and in some states, obligations in connection with obtaining contractors’ licenses. MasTec also generally warrants the work it performs for a one to two year period following substantial completion of a project. MasTec has not historically accrued any reserves for potential warranty claims as they have been immaterial.
	Concentrations of Risk. The Company had approximately 290 customers as of March 31, 2014. For the three months ended March 31, 2014 and 2013, the Company derived 73% and 69%, respectively, of revenues from its top ten customers. See Note 15 - Segments and Related Information for significant customer revenue concentration information.

Related_Party_Transactions

Related Party Transactions	3 Months Ended
	Mar. 31, 2014
Related Party Transactions [Abstract]	'
Related Party Transactions	'
	Related Party Transactions
	MasTec purchases, rents and leases equipment used in its business from a number of different vendors on a non-exclusive basis, including Cross Country Pipeline Supply, Inc. (“CCP”), in which MasTec invested $15 million for a 14.85% ownership interest effective November 8, 2013. Juan Carlos Mas, who is the brother of Jorge Mas, Chairman of MasTec's Board of Directors, and Jose Mas, MasTec's Chief Executive Officer, serves as the chairman of CCP. In addition, an entity owned by the Mas family, including Jorge and Jose Mas, is a minority shareholder of CCP. MasTec paid CCP approximately $0.9 million for equipment rentals, leases and servicing for the three month period ended March 31, 2014.
	MasTec leases employees to a customer, in which Jorge Mas and Jose Mas own a minority interest. For the three month periods ended March 31, 2014 and 2013, MasTec charged to the customer approximately $0.2 million and $0.1 million, respectively. As of both March 31, 2014 and December 31, 2013, receivables of $0.1 million attributable to this arrangement were outstanding. The Company also provides satellite communication services to this customer. For both of the three month periods ended March 31, 2014 and 2013, revenues relating to this customer were approximately $0.3 million. As of both March 31, 2014 and December 31, 2013, outstanding receivables from this arrangement totaled $0.4 million.
	Split Dollar and Deferred Bonus Agreements
	MasTec has a split dollar agreement with Jorge Mas. The Company made no payments in connection with this agreement in either of the three month periods ended March 31, 2014 or 2013. MasTec also has a split dollar agreement and a deferred bonus agreement with Jose Mas. For the three month periods ended March 31, 2014 and 2013, no payments were made in connection with the agreements for Jose Mas. As of March 31, 2014 and December 31, 2013, life insurance assets associated with these agreements of $10.1 million and $10.2 million, respectively, are included within other long-term assets in the condensed unaudited consolidated balance sheets. For additional information regarding the foregoing agreements with Jorge Mas and Jose Mas, see Note 17 - Related Party Transactions in the notes to the Company's consolidated financial statements included in its Annual Report on Form 10-K for the year ended December 31, 2013.

Supplemental_Guarantor_Condens

Supplemental Guarantor Condensed Unaudited Consolidating Financial Information	3 Months Ended
	Mar. 31, 2014
Condensed Unaudited Financial Statements, Supplemental Guarantor Information [Abstract]	'
Supplemental Guarantor Condensed Unaudited Consolidating Financial Information	'
	Supplemental Guarantor Condensed Unaudited Consolidating Financial Information
	The 2011 Convertible Notes, 2009 Convertible Notes and 4.875% Senior Notes are fully and unconditionally guaranteed on an unsecured, unsubordinated, joint and several basis by certain of the Company's existing and future 100%-owned direct and indirect domestic subsidiaries that are each guarantors of the Company's 2013 Credit Facility or other outstanding indebtedness (the “Guarantor Subsidiaries”).  Certain subsidiaries included in the Company's Guarantor Subsidiaries, which are minor individually and in the aggregate, do not guarantee the 4.875% Senior Notes. The Company's subsidiaries organized outside of the United States and certain domestic subsidiaries (collectively, the “Non-Guarantor Subsidiaries”) do not guarantee any of these notes. A Guarantor Subsidiary's guaranty is subject to release in certain customary circumstances, including upon the sale of a majority of the capital stock or substantially all of the assets of such Subsidiary Guarantor, if such Subsidiary Guarantor's guarantee under our 2013 Credit Facility and other indebtedness is released or discharged (other than due to payment under such guarantee), or when the requirements for legal defeasance are satisfied or the obligations are discharged in accordance with the related indentures.
	The following supplemental financial information sets forth the condensed unaudited consolidating balance sheets and the condensed unaudited consolidating statements of operations and comprehensive income and cash flows for the parent company (MasTec, Inc.), the Guarantor Subsidiaries on a combined basis, the Non-Guarantor Subsidiaries on a combined basis and the eliminations necessary to arrive at the information for the Company as reported on a consolidated basis. Eliminations represent adjustments to eliminate investments in subsidiaries and intercompany balances and transactions between or among MasTec, Inc., the Guarantor Subsidiaries and the Non-Guarantor Subsidiaries.  Investments in subsidiaries are accounted for using the equity method for this presentation.
	.
	CONDENSED UNAUDITED CONSOLIDATING STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME (in millions)
	For the Three Months Ended March 31, 2014	MasTec, Inc.			Guarantor			Non-Guarantor			Eliminations			Consolidated
					Subsidiaries			Subsidiaries						MasTec, Inc.
	Revenue	$	—		$	793.1		$	170.9		$	—		$	964
	Costs of revenue, excluding depreciation and amortization	—			689.8			151.3			—			841.1
	Depreciation and amortization	—			27.4			6.1			—			33.5
	General and administrative expenses	0.6			47.3			5.4			—			53.3
	Interest expense, net	—			11.7			0.3			—			12
	Other (income) expense, net	—			(2.1		)	0.1			—			(2.0		)
	(Loss) income from continuing operations before income taxes	$	(0.6	)	$	19		$	7.7		$	—		$	26.1
	Benefit from (provision for) income taxes	0.2			(9.4		)	(0.7		)	—			(9.9		)
	Net (loss) income from continuing operations	$	(0.4	)	$	9.6		$	7		$	—		$	16.2
	Net loss from discontinued operations	—			—			(0.1		)	—			(0.1		)
	Equity in income from subsidiaries, net of tax	16.4			—			—			(16.4		)	—
	Net income (loss)	$	16		$	9.6		$	6.9		$	(16.4	)	$	16.1
	Net income attributable to non-controlling interests	—			—			0.1			—			0.1
	Net income (loss) attributable to MasTec, Inc.	$	16		$	9.6		$	6.8		$	(16.4	)	$	16
	Comprehensive income (loss)	$	10.6		$	9.5		$	1.6		$	(11.0	)	$	10.7
	For the Three Months Ended March 31, 2013	MasTec, Inc.			Guarantor			Non-Guarantor			Eliminations			Consolidated
					Subsidiaries			Subsidiaries						MasTec, Inc.
	Revenue	$	—		$	843.1		$	77.2		$	(1.7	)	$	918.6
	Costs of revenue, excluding depreciation and amortization	—			721.2			72			(1.7		)	791.5
	Depreciation and amortization	—			28.9			2.9			—			31.8
	General and administrative expenses	0.3			45.1			3.5			—			48.9
	Interest expense, net	—			10			—			—			10
	Loss on extinguishment of debt	—			5.6			—			—			5.6
	Other income, net	—			(0.9		)	—			—			(0.9		)
	(Loss) income from continuing operations before income taxes	$	(0.3	)	$	33.2		$	(1.2	)	$	—		$	31.7
	Benefit from (provision for) income taxes	0.1			(13.0		)	0.5			—			(12.4		)
	Net (loss) income from continuing operations	$	(0.2	)	$	20.2		$	(0.7	)	$	—		$	19.3
	Net loss from discontinued operations	—			—			(0.9		)	—			(0.9		)
	Equity in income from subsidiaries, net of tax	18.8			—			—			(18.8		)	—
	Net income (loss)	$	18.6		$	20.2		$	(1.6	)	$	(18.8	)	$	18.4
	Net income attributable to non-controlling interests	—			—			0			—			0
	Net income (loss) attributable to MasTec, Inc.	$	18.6		$	20.2		$	(1.6	)	$	(18.8	)	$	18.4
	Comprehensive income (loss)	$	17.8		$	20.5		$	(2.5	)	$	(18.0	)	$	17.8
	CONDENSED UNAUDITED CONSOLIDATING BALANCE SHEETS (in millions)
	As of March 31, 2014	MasTec, Inc.			Guarantor			Non-Guarantor			Eliminations			Consolidated
					Subsidiaries			Subsidiaries						MasTec, Inc.
	Assets
	Current assets, including discontinued operations	$	—		$	1,165.30		$	192.6		$	—		$	1,357.90
	Property and equipment, net	—			435.9			73.7			—			509.6
	Goodwill and other intangible assets, net	—			931.8			152.7			—			1,084.50
	Net investments in and advances to (from) consolidated affiliates	1,022.50			173.9			(25.0		)	(1,171.4		)	—
	Other long-term assets, including discontinued operations	9.3			36.9			15.2			—			61.4
	Total assets	$	1,031.80		$	2,743.80		$	409.2		$	(1,171.4	)	$	3,013.40
	Liabilities and Equity
	Total current liabilities	$	—		$	735.7		$	84.7		$	—		$	820.4
	Long-term debt	—			833.3			8			—			841.3
	Other liabilities	—			236.7			78.2			—			314.9
	Total liabilities	$	—		$	1,805.70		$	170.9		$	—		$	1,976.60
	Total equity	$	1,031.80		$	938.1		$	238.3		$	(1,171.4	)	$	1,036.80
	Total liabilities and equity	$	1,031.80		$	2,743.80		$	409.2		$	(1,171.4	)	$	3,013.40
	As of December 31, 2013	MasTec, Inc.			Guarantor			Non-Guarantor			Eliminations			Consolidated
					Subsidiaries			Subsidiaries						MasTec, Inc.
	Assets
	Current assets, including discontinued operations	$	—		$	1,155.90		$	150.3		$	—		$	1,306.20
	Property and equipment, net	—			420.2			67.9			—			488.1
	Goodwill and other intangible assets, net	—			933.9			132.2			—			1,066.10
Net investments in and advances to (from) consolidated affiliates	1,006.80			172.4			(24.1		)	(1,155.1		)	—
Other long-term assets, including discontinued operations	9.3			36.2			15.1			—			60.6
Total assets	$	1,016.10		$	2,718.60		$	341.4		$	(1,155.1	)	$	2,921.00
Liabilities and Equity
Total current liabilities	$	—		$	773.3		$	53.4		$	—		$	826.7
Long-term debt	—			760.9			4.5			—			765.4
Other liabilities	—			236.7			71.1			—			307.8
Total liabilities	$	—		$	1,770.90		$	129		$	—		$	1,899.90
Total equity	$	1,016.10		$	947.7		$	212.4		$	(1,155.1	)	$	1,021.10
Total liabilities and equity	$	1,016.10		$	2,718.60		$	341.4		$	(1,155.1	)	$	2,921.00
CONDENSED UNAUDITED CONSOLIDATING STATEMENTS OF CASH FLOWS (in millions)
For the Three Months Ended March 31, 2014	MasTec, Inc.			Guarantor			Non-Guarantor			Eliminations			Consolidated
				Subsidiaries			Subsidiaries						MasTec, Inc.
Net cash (used in) provided by operating activities	$	(0.3	)	$	15.2		$	(35.3	)	$	—		$	(20.4	)
Cash flows (used in) provided by investing activities:
Cash paid for acquisitions, net of cash acquired	—			(23.8		)	—			—			(23.8		)
Capital expenditures	—			(32.6		)	(3.0		)	—			(35.6		)
Proceeds from sale of property and equipment	—			3.4			—			—			3.4
Payments for other investments	—			(1.1		)	—			—			(1.1		)
Net cash used in investing activities	$	—		$	(54.1	)	$	(3.0	)	$	—		$	(57.1	)
Cash flows provided by (used in) financing activities:
Proceeds from (repayments of) credit facility	—			76.5			—			—			76.5
Repayments of other borrowings and capital lease obligations	—			(12.9		)	(0.9		)	—			(13.8		)
Excess tax benefits and net proceeds from stock-based awards	1.1			0.7			—			—			1.8
Payments of financing costs	—			(0.2		)	—			—			(0.2		)
Net financing activities and advances (to) from consolidated affiliates	(0.8		)	(24.7		)	25.5			—			—
Net cash provided by financing activities	$	0.3		$	39.4		$	24.6		$	—		$	64.3
Net increase (decrease) in cash and cash equivalents	—			0.5			(13.7		)	—			(13.2		)
Net effect of currency translation on cash	—			—			(0.5		)	—			(0.5		)
Cash and cash equivalents - beginning of period	—			5.3			17.7			—			23
Cash and cash equivalents - end of period	$	—		$	5.8		$	3.5		$	—		$	9.3
Cash and cash equivalents of discontinued operations	$	—		$	—		$	—		$	—		$	—
Cash and cash equivalents of continuing operations	$	—		$	5.8		$	3.5		$	—		$	9.3
For the Three Months Ended March 31, 2013	MasTec, Inc.			Guarantor			Non-Guarantor			Eliminations			Consolidated
				Subsidiaries			Subsidiaries						MasTec, Inc.
Net cash (used in) provided by operating activities	$	(0.6	)	$	50.3		$	(23.6	)	$	—		$	26.1
Cash flows (used in) provided by investing activities:
Cash paid for acquisitions, net of cash acquired	—			(4.7		)	—			—			(4.7		)
Capital expenditures	—			(25.4		)	(0.4		)	—			(25.8		)
Proceeds from sale of property and equipment	—			3.4			—			—			3.4
Net cash used in investing activities	$	—		$	(26.7	)	$	(0.4	)	$	—		$	(27.1	)
Cash flows provided by (used in) financing activities:
(Repayments of) proceeds from credit facility	$	—		$	(134.0	)	$	—		$	—		$	(134.0	)
Proceeds from senior notes, net	—			250			—			—			250
Repayments of other borrowings and capital lease obligations	—			(19.1		)	—			—			(19.1		)
Excess tax benefits and net proceeds from stock-based awards	2.8			0.7			—			—			3.5
Payments of acquisition-related contingent consideration	—			(5.0		)	—			—			(5.0		)
Payments of financing costs, including call premiums on extinguishment of debt	—			(11.0		)	—			—			(11.0		)
Net financing activities and advances (to) from consolidated affiliates	(2.2		)	(12.9		)	15.1			—			—
Net cash provided by financing activities	$	0.6		$	68.7		$	15.1		$	—		$	84.4
Net increase (decrease) in cash and cash equivalents	—			92.3			(8.9		)	—			83.4
Net effect of currency translation on cash	—			(0.1		)	—			—			(0.1		)
Cash and cash equivalents - beginning of period	—			12.7			14.1			—			26.8
Cash and cash equivalents - end of period	$	—		$	104.9		$	5.2		$	—		$	110.1
Cash and cash equivalents of discontinued operations	$	—		$	—		$	0.9		$	—		$	0.9
Cash and cash equivalents of continuing operations	$	—		$	104.9		$	4.3		$	—		$	109.2

Business_Basis_of_Presentation1

Business, Basis of Presentation and Significant Accounting Policies (Policies)	3 Months Ended
	Mar. 31, 2014
Accounting Policies [Abstract]	'
Nature of the Business	'
	Nature of the Business
	MasTec, Inc. (collectively with its subsidiaries, “MasTec” or the “Company”) is a leading infrastructure construction company operating mainly throughout North America across a range of industries. The Company’s primary activities include the engineering, building, installation, maintenance and upgrade of energy, utility and communications infrastructure, such as: petroleum and natural gas pipeline infrastructure; wireless, wireline and satellite communications; electrical utility transmission and distribution; power generation; and industrial infrastructure. MasTec’s customers are in these industries. MasTec reports its results in five reportable segments: (1) Communications; (2) Oil and Gas; (3) Electrical Transmission; (4) Power Generation and Industrial; and (5) Other. See Note 15 - Segments and Related Information.
Basis of Presentation	'
	Basis of Presentation
	The accompanying condensed unaudited consolidated financial statements have been prepared in accordance with accounting principles generally accepted in the United States (“U.S. GAAP”) for interim financial information and with the instructions for Form 10-Q and Rule 10-01 of Regulation S-X. Pursuant to these rules and regulations, certain information and footnote disclosures normally included in the annual consolidated financial statements prepared in accordance with U.S. GAAP have been condensed or omitted. The accompanying condensed consolidated balance sheet as of December 31, 2013 is derived from the Company’s audited financial statements as of that date. Because certain information and footnote disclosures have been condensed or omitted, these condensed unaudited consolidated financial statements should be read in conjunction with the audited consolidated financial statements and notes thereto as of and for the year ended December 31, 2013 contained in the Company’s most recent Annual Report on Form 10-K. In management’s opinion, all normal and recurring adjustments considered necessary for a fair presentation of the financial position, results of operations and cash flows for the periods presented have been included. Certain prior year amounts have been reclassified to conform to the current period presentation. Interim period operating results do not necessarily indicate the results that may be expected for any other interim period or for the full fiscal year. The Company believes that the disclosures made in these condensed unaudited consolidated financial statements are adequate to make the information not misleading.
Reclassifications	'
	Certain prior year amounts have been reclassified to conform to the current period presentation.
Principles of Consolidation	'
	Principles of Consolidation
	The accompanying condensed unaudited consolidated financial statements include MasTec, Inc. and its subsidiaries and include the accounts of all majority owned subsidiaries over which the Company exercises control and, when applicable, entities in which the Company has a controlling financial interest. Other parties’ interests in companies for which MasTec exercises control and has a controlling financial interest are reported as non-controlling interests within equity. Net income or loss attributable to non-controlling interests is reported as a separate line item below net income. The Company’s investments in entities in which the Company does not have a controlling interest, but has the ability to exert significant influence, are accounted for using the equity method of accounting. Equity method investments are recorded as long-term assets in the condensed unaudited consolidated balance sheets. Income or loss from these investments is recorded in other income or expense, net, in the condensed unaudited consolidated statements of operations. The cost method is used for investments in entities in which the Company does not have the ability to exert significant influence. All significant intercompany balances and transactions have been eliminated in consolidation. The assets and liabilities of foreign subsidiaries are translated into U.S. dollars at period-end exchange rates, with resulting translation gains or losses accumulated within other comprehensive income or loss. Revenue and expenses are translated into U.S. dollars at average rates of exchange prevailing during the applicable period. Gains or losses resulting from transactions executed in a foreign currency are included in other income or expense, net. The Company does not currently have any subsidiaries that operate in highly inflationary environments. The results of operations and financial position of any discontinued operations are aggregated and presented separately from the Company's continuing operations in the condensed unaudited consolidated financial statements for all periods presented.
Translation of Foreign Currencies	'
	The assets and liabilities of foreign subsidiaries are translated into U.S. dollars at period-end exchange rates, with resulting translation gains or losses accumulated within other comprehensive income or loss. Revenue and expenses are translated into U.S. dollars at average rates of exchange prevailing during the applicable period. Gains or losses resulting from transactions executed in a foreign currency are included in other income or expense, net. The Company does not currently have any subsidiaries that operate in highly inflationary environments.
Management Estimates	'
	Management Estimates
	The preparation of financial statements in conformity with U.S. GAAP requires management to make estimates and assumptions that affect the amounts reported in the financial statements and accompanying notes. Key estimates include: the recognition of revenue, in particular, on long-term construction contracts, including estimates of costs to complete projects and provisions for contract losses; allowances for doubtful accounts; accrued self-insured claims; estimated fair values of goodwill and intangible assets, acquisition-related contingent consideration, assets and liabilities classified as held-for-sale, convertible debt obligations and investments in cost and equity method investees; asset lives used in computing depreciation and amortization, including amortization of intangible assets; share-based compensation; accounting for income taxes; and the estimated impact of contingencies and ongoing litigation. While management believes that such estimates are fair when considered in conjunction with the consolidated financial position and results of operations taken as a whole, actual results could differ from those estimates and such differences may be material to the condensed unaudited consolidated financial statements.
Significant Accounting Policies	'
	Significant Accounting Policies
	Revenue Recognition
	Revenues are derived from projects performed under master and other service agreements as well as from fixed price contracts for specific projects or jobs requiring the construction and installation of an entire infrastructure system or specified units within an entire infrastructure system. Revenue and related costs for master and other service agreements billed on a time and materials basis are recognized as the services are rendered. The Company also performs services under master and other service agreements on a fixed fee basis, under which MasTec furnishes specified units of service for a fixed price per unit of service and revenue is recognized as the services are rendered. Revenues from fixed price contracts provide for a fixed amount of revenue for the entire project, subject to certain additions for changed scope or specifications. Revenues from these contracts are recognized using the percentage-of-completion method. Under this method, the percentage of revenue to be recognized for a given project is measured by the percentage of costs incurred to date on the contract to the total estimated costs for the contract. Such contracts provide that the customer accept completion of progress to date and compensate the Company for services rendered, which may be measured in terms of costs incurred, units installed, hours expended or some other measure of progress.
	The Company may incur costs subject to change orders, whether approved or unapproved by the customer, and/or claims related to certain contracts. Management determines the probability that such costs will be recovered based upon evidence such as engineering studies and legal opinions, past practices with the customer, specific discussions, correspondence or preliminary negotiations with the customer. The Company treats project costs as a cost of contract performance in the period incurred if it is not probable that the costs will be recovered, or defers costs and/or recognizes revenue up to the amount of the related cost if it is probable that the contract price will be adjusted and can be reliably estimated. As of March 31, 2014 and December 31, 2013, the Company had approximately $163 million and $79 million, respectively, of change orders and/or claims that had been included as contract price adjustments on certain contracts that were in the process of being negotiated in the normal course of business, including arbitration and other proceedings. These contract price adjustments represent management's best estimate of additional contract revenues that have been earned and that management believes are probable of collection. The amounts ultimately realized upon final acceptance by its customers could be higher or lower than such estimated amounts, which are primarily expected to be billed and collected within one year. The $84 million increase in change orders and/or claims since December 31, 2013 is primarily due to a project in our Oil and Gas segment, which amounts have been approved in principle subsequent to March 31, 2014.
	Except for adoption of the accounting pronouncement discussed below, there have been no material changes to the significant accounting policies described in the Company’s Annual Report on Form 10-K for the year ended December 31, 2013.
Revenue Recognition	'
	Revenue Recognition
	Revenues are derived from projects performed under master and other service agreements as well as from fixed price contracts for specific projects or jobs requiring the construction and installation of an entire infrastructure system or specified units within an entire infrastructure system. Revenue and related costs for master and other service agreements billed on a time and materials basis are recognized as the services are rendered. The Company also performs services under master and other service agreements on a fixed fee basis, under which MasTec furnishes specified units of service for a fixed price per unit of service and revenue is recognized as the services are rendered. Revenues from fixed price contracts provide for a fixed amount of revenue for the entire project, subject to certain additions for changed scope or specifications. Revenues from these contracts are recognized using the percentage-of-completion method. Under this method, the percentage of revenue to be recognized for a given project is measured by the percentage of costs incurred to date on the contract to the total estimated costs for the contract. Such contracts provide that the customer accept completion of progress to date and compensate the Company for services rendered, which may be measured in terms of costs incurred, units installed, hours expended or some other measure of progress.
	The Company may incur costs subject to change orders, whether approved or unapproved by the customer, and/or claims related to certain contracts. Management determines the probability that such costs will be recovered based upon evidence such as engineering studies and legal opinions, past practices with the customer, specific discussions, correspondence or preliminary negotiations with the customer. The Company treats project costs as a cost of contract performance in the period incurred if it is not probable that the costs will be recovered, or defers costs and/or recognizes revenue up to the amount of the related cost if it is probable that the contract price will be adjusted and can be reliably estimated. As of March 31, 2014 and December 31, 2013, the Company had approximately $163 million and $79 million, respectively, of change orders and/or claims that had been included as contract price adjustments on certain contracts that were in the process of being negotiated in the normal course of business, including arbitration and other proceedings. These contract price adjustments represent management's best estimate of additional contract revenues that have been earned and that management believes are probable of collection. The amounts ultimately realized upon final acceptance by its customers could be higher or lower than such estimated amounts, which are primarily expected to be billed and collected within one year. The $84 million increase in change orders and/or claims since December 31, 2013 is primarily due to a project in our Oil and Gas segment, which amounts have been approved in principle subsequent to March 31, 2014.
New Accounting Pronouncements	'
	New Accounting Pronouncements
	Accounting Standards Not Yet Adopted
	In April 2014, the Financial Accounting Standards Board (“FASB”) issued Accounting Standards Update (“ASU”) 2014-08, Presentation of Financial Statements (Topic 205) and Property, Plant, and Equipment (Topic 360): Reporting Discontinued Operations and Disclosures of Disposals of Components of an Entity (“ASU 2014-08”). ASU 2014-08 changes the requirements for reporting discontinued operations and requires additional disclosures about discontinued operations. Only disposals of components of an entity representing a strategic shift that has, or will have, a major effect on an entity’s operations and financial results should be reported as discontinued operations under ASU 2014-08. Examples include a disposal of a major geographical area, a major line of business, or a major equity method investment. ASU 2014-08 also requires expanded disclosures about discontinued operations and requires disclosures about individually significant dispositions that do not qualify as discontinued operations. ASU 2014-08 is effective prospectively for fiscal years, and interim periods within those years, beginning after December 15, 2014. Early adoption is permitted only for disposals that have not been previously reported. The Company is currently evaluating the potential impact of this ASU on its condensed unaudited consolidated financial statements.
	Recently Adopted Accounting Pronouncements
	In July 2013, the FASB issued ASU 2013-11, Income Taxes (Topic 740): Presentation of an Unrecognized Tax Benefit When a Net Operating Loss Carryforward, a Similar Tax Loss, or a Tax Credit Carryforward Exists (a consensus of the FASB Emerging Issues Task Force) (“ASU 2013-11”).  ASU 2013-11 provides guidance on the presentation in the financial statements of an unrecognized tax benefit, or a portion of an unrecognized tax benefit, and explains that unrecognized tax benefits should be presented as a reduction to deferred tax assets for net operating loss carryforwards, similar tax losses or tax credit carryforwards. To the extent a net operating loss carryforward, similar tax loss or tax credit carryforward is not available as of the reporting date under the tax law of the applicable jurisdiction, or the tax law of the applicable jurisdiction does not require the entity to use, and the entity does not intend to use, the deferred tax asset for such purpose, the unrecognized tax benefit should be presented in the financial statements as a liability and should not be combined with deferred tax assets. ASU 2013-11 applies to all entities that have unrecognized tax benefits when a net operating loss carryforward, similar tax loss, or tax credit carryforward exists as of the reporting date. ASU 2013-11 is effective prospectively for fiscal years, and interim periods within those years, beginning after December 15, 2013. Retrospective application is permitted. The Company adopted ASU 2013-11 as of January 1, 2014. The adoption of this ASU did not have a material impact on the condensed unaudited consolidated financial statements.

Earnings_Per_Share_Tables

Earnings Per Share (Tables)	3 Months Ended
	Mar. 31, 2014
Earnings Per Share [Line Items]	'
Schedule of Earnings Per Share Information	'
	The following table provides details underlying the Company’s earnings per share calculations for the periods indicated (in thousands):
		For the Three Months Ended March 31,
		2014			2013
	Net income attributable to MasTec:
	Net income, continuing operations - basic (a)	$	16,145		$	19,317
	Interest expense, net of tax, 2009 Convertible Notes	78			77
	Net income, continuing operations - diluted	$	16,223		$	19,394
	Net loss from discontinued operations - basic and diluted (a)	(122		)	(947		)
	Net income attributable to MasTec - diluted	$	16,101		$	18,447
	Weighted average shares outstanding:
	Weighted average shares outstanding - basic	77,345			76,608
	Dilutive common stock equivalents	850			785
	Dilutive premium shares, 2011 Convertible Notes	7,621			5,895
	Dilutive shares, 2009 Convertible Notes	806			806
	Weighted average shares outstanding - diluted	86,622			84,094
	(a)	Calculated as total net income less amounts attributable to non-controlling interests.
2011 Convertible Notes [Member]	'
Earnings Per Share [Line Items]	'
Schedule of Convertible Note Premium Share Information	'
	The calculations underlying the number of premium shares included in the Company’s diluted share count for the periods indicated are as follows (in thousands, except per share amounts):
		As of and for the Three Months Ended March 31,
		2014						2013
	Premium Share Information:	2011 4.0%			2011 4.25%			2011 4.0%		2011 4.25%
		Notes			Notes			Notes		Notes
	Number of conversion shares, principal amount	6,683			6,268			6,683		6,268
	Weighted average actual per share price	$	37.96		$	37.96		$	28.68	$	28.68
	Weighted average premium value	$	148,360		$	140,925		$	86,316	$	82,735
	Weighted average equivalent premium shares	3,909			3,712			3,010		2,885

Acquisitions_Tables

Acquisitions (Tables)	3 Months Ended
	Mar. 31, 2014
Business Acquisition [Line Items]	'
Schedule of Business Acquisitions, Pro Forma Information	'
	The unaudited supplemental pro forma financial information presented below has been prepared by adjusting the historical results of MasTec to include the historical results of the acquired businesses described above. The unaudited supplemental pro forma combined historical results were then adjusted (i) to remove one-time acquisition costs; (ii) to increase amortization expense resulting from the incremental intangible assets acquired in such acquisitions; (iii) to increase interest expense as a result of the cash consideration paid; and (iv) to reduce interest expense from the repayment of acquired debt. The unaudited supplemental pro forma financial information does not include any adjustments to reflect the impact of cost savings or other synergies that may result from these acquisitions. As noted above, the unaudited supplemental pro forma financial information does not purport to be indicative of the actual results that would have been achieved by the combined companies for the periods presented or that may be achieved by the combined companies in the future.
		For the Three Months Ended March 31,
		2014			2013
	Pro forma financial information:	(unaudited, in millions)
	Revenue	$	964		$	1,029.10
	Net income from continuing operations	$	16.2		$	24.1
	Results of Businesses Acquired
	Revenues and net income resulting from the year over year incremental impact of acquired businesses, which are included within the Company's consolidated results of operations for the years indicated, are as follows (in millions):
		For the Three Months Ended March 31,
		2014			2013
	Year over year impact of acquired businesses:	(unaudited, in millions)
	Revenue	$	119.8		$	43.1
	Net income from continuing operations	$	1		$	1.8
	The above results do not include acquisition costs of $0.2 million and $0.4 million for the three month periods ended March 31, 2014 and March 31, 2013, respectively. The above results also do not include interest expense associated with consideration paid for these acquisitions.
2013 Acquisitions [Member]	'
Business Acquisition [Line Items]	'
Schedule of Business Acquisitions, Measurement Period Adjustments	'
	Measurement period adjustments associated with the Company's 2013 acquisitions have been reflected in the Company's December 31, 2013 consolidated balance sheet as follows (in millions):
	As of December 31, 2013		As Previously Reported			Measurement Period Adjustments		As Revised
	Current assets		$	1,306.00		$	0.2	$	1,306.20
	Goodwill		$	899.4		$	1.1	$	900.5
	Current liabilities		$	825.5		$	1.2	$	826.7
	Long-term deferred tax liabilities, net		$	154.9		$	0.1	$	155

Discontinued_Operations_Tables

Discontinued Operations (Tables) (Globetec [Member])	3 Months Ended
	Mar. 31, 2014
Globetec [Member]	'
Discontinued Operations Disclosures [Line Items]	'
Summary of Assets, Liabilities and Results of Operations from Discontinued Operations	'
	The following table contains a summary of the contingent assets and liabilities associated with Globetec that were retained by the Company as of March 31, 2014 and as of December 31, 2013 (in millions):
		March 31,			December 31,
		2014			2013
	Current assets	$	3.4		$	2.3
	Long-term assets	10.1			10.1
	Assets of discontinued operations	$	13.5		$	12.4
	Current liabilities of discontinued operations	$	1.3		$	1.2
	The following table presents results from discontinued operations associated with the Globetec operation for the periods indicated (in millions):
		For the Three Months Ended March 31, 2013
	Revenue	$	6.3
	Loss from operations, before tax	(1.2		)
	Benefit from income taxes	0.3
	Net loss from discontinued operations	$	(0.9	)

Goodwill_and_Other_Intangible_1

Goodwill and Other Intangible Assets (Tables)	3 Months Ended
	Mar. 31, 2014
Goodwill and Intangible Assets Disclosure [Abstract]	'
Rollforward of Goodwill by Segment	'
	The following table provides a reconciliation of changes in goodwill by reportable segment (in millions):
		Communications			Oil and Gas				Electrical				Power				Total Goodwill
									Transmission				Generation and Industrial
	Balance as of December 31, 2013	$	327.9		$	305.2			$	149.8			$	117.6			$	900.5
	Additions from new business combinations	14.5			—				—				—				14.5
	Currency translation adjustments	—			(2.1		)		—				—				(2.1		)
	Balance as of March 31, 2014	$	342.4		$	303.1			$	149.8			$	117.6			$	912.9
Rollforward of Other Intangible Assets	'
	The following table provides a reconciliation of changes in other intangible assets (in millions):
			Other Intangible Assets
			Non-amortizing							Amortizing
			Trade Names			Pre-Qualifications				Customer Relationships and Backlog				Other (a)				Total
	Other intangible assets, gross carrying amount as of December 31, 2013		$	34.8		$	59.4			$	128.4			$	22.5			$	245.1
	Accumulated amortization									$	(67.7	)		$	(11.8	)		$	(79.5	)
	Other intangible assets, net, as of December 31, 2013		$	34.8		$	59.4			$	60.7			$	10.7			$	165.6
	Additions from new business combinations		—			—				11.7				0.3				12
	Amortization expense									(4.2		)		(0.4		)		(4.6		)
	Currency translation adjustments		—			(1.1		)		(0.2		)		(0.1		)		(1.4		)
	Other intangible assets, net, as of March 31, 2014		$	34.8		$	58.3			$	68			$	10.5			$	171.6
	(a) Consists principally of trade names and non-compete agreements.

Fair_Value_of_Financial_Instru1

Fair Value of Financial Instruments (Tables)	3 Months Ended
	Mar. 31, 2014
Fair Value Disclosures [Abstract]	'
Schedule Of Fair Values Of Financial Assets And Liabilities Measured On A Recurring Basis	'
	The fair values of financial assets and liabilities measured on a recurring basis were determined using the following inputs as of the dates indicated (in millions):
				Fair Value Measurements
				Using Inputs Considered as Significant
		Fair Value as of		Level 1		Level 2		Level 3
		31-Mar-14
	Assets
	Life insurance surrender values	$	5.5	$	5.5
	Liabilities
	Acquisition-related contingent consideration	$	170.3					$	170.3
				Fair Value Measurements
				Using Inputs Considered as Significant
		Fair Value as of		Level 1		Level 2		Level 3
		31-Dec-13
	Assets
	Life insurance surrender values	$	5.3	$	5.3
	Liabilities
	Acquisition-related contingent consideration	$	162.9					$	162.9
Schedule of Fair Values of Financial Assets And Liabilities Measured On A Non-Recurring Basis	'
	Carrying amounts and estimated fair values of selected financial instruments measured on a non-recurring basis as of the dates indicated were as follows (in millions):
		March 31, 2014				December 31, 2013
		Carrying		Fair		Carrying				Fair
		Amount		Value		Amount				Value
	4.875% Senior Notes	$	400	$	390.5	$	400			$	380
	2009 Convertible Notes	$	12.6	$	35	$	12.6			$	26.6
	2011 Convertible Notes	$	199.7	$	563.2	$	198.3			$	428.3

Accounts_Receivable_Net_of_All1

Accounts Receivable, Net of Allowance (Tables) (Trade Accounts Receivable [Member])	3 Months Ended
	Mar. 31, 2014
Trade Accounts Receivable [Member]	'
Schedule of Accounts Receivable, Net of Allowance [Line Items]	'
Schedule Of Accounts Receivable, Net of Allowance	'
	The following table provides details of accounts receivable, net of allowance, as of the dates indicated (in millions):
		March 31,			December 31,
		2014			2013
	Contract billings	$	627.1		$	606.5
	Retainage	135.6			159.3
	Costs and earnings in excess of billings	448.6			384.6
	Accounts receivable, gross	$	1,211.30		$	1,150.40
	Less allowance for doubtful accounts	(15.7		)	(15.8		)
	Accounts receivable, net	$	1,195.60		$	1,134.60

Debt_Tables

Debt (Tables)	3 Months Ended
	Mar. 31, 2014
Debt Disclosure [Abstract]	'
Schedule of Long Term Debt Instruments	'
	The following table provides details of the carrying values of debt as of the dates indicated (in millions):
	Description		Maturity Date	March 31,				December 31,
				2014				2013
	Credit facility		October 29, 2018	$	128.6			$	53
	4.875% senior notes		March 15, 2023	400				400
	2011 4.0% senior convertible notes		June 15, 2014	104.6				103.8
	2011 4.25% senior convertible notes		December 15, 2014	95.1				94.5
	2009 4.0% senior convertible notes		June 15, 2014	9.6				9.6
	2009 4.25% senior convertible notes		December 15, 2014	3				3
	Capital lease obligations, weighted average interest rate of 2.9%		In installments through March 30, 2020	123.2				126
	Notes payable for equipment, weighted average interest rate of 3.0%		In installments through May 1, 2018	30.1				26.9
	Total debt			$	894.2			$	816.8
	Less current maturities			(52.9		)		(51.4		)
	Long-term debt			$	841.3			$	765.4
Schedule of Interest Expense, Net	'
	The following table provides details of interest expense, net, for the periods indicated (in millions):
		For the Three Months Ended March 31,
		2014			2013
	Interest expense:
	Contractual and other interest expense	$	9.7		$	7.9
	Accretion of senior convertible note discount	1.4			1.3
	Amortization of deferred financing costs	0.9			0.9
	Total interest expense	$	12		$	10.1
	Interest income	0			(0.1		)
	Interest expense, net	$	12		$	10

Property_and_Equipment_Net_Tab

Property and Equipment, Net (Tables)	3 Months Ended
	Mar. 31, 2014
Property, Plant and Equipment [Abstract]	'
Schedule of Property And Equipment, Net	'
	The following table provides details of property and equipment, net, including property and equipment held under capital leases as of the dates indicated (in millions):
		March 31,			December 31,
		2014			2013
	Land	$	4.6		$	4.8
	Buildings and leasehold improvements	17.6			18
	Machinery and equipment	752.2			727.1
	Office furniture and equipment	108			102.5
	Construction in progress	16.9			11
	Total property and equipment	$	899.3		$	863.4
	Less accumulated depreciation and amortization	(389.7		)	(375.3		)
	Property and equipment, net	$	509.6		$	488.1

StockBased_Compensation_and_Ot1

Stock-Based Compensation and Other Employee Benefit Plans (Tables)	3 Months Ended
	Mar. 31, 2014
Share-based Compensation [Abstract]	'
Summary of Restricted Share Award Activity	'
	Activity, restricted share awards:	Restricted		Weighted Average Grant Date
		Shares		Fair Value
	Non-vested restricted shares, as of December 31, 2013	1,123,545		$	23.78
	Granted	326,442		41.39
	Vested	(141,138	)	19.41
	Canceled/forfeited	(13,450	)	16.05
	Non-vested restricted shares, as of March 31, 2014	1,295,399		$	28.77
Summary of Stock Option Activity	'
	Activity, stock options:	Stock		Per Share Weighted Average			Weighted Average	Aggregate Intrinsic
		Options		Exercise Price			Remaining	Value (a)
							Contractual Life (in years)	(in millions)
	Options outstanding as of December 31, 2013	495,571		$	11.17		1.96	$	10.7
	Exercised	(200,900	)	9.77
	Canceled/forfeited	—		—
	Options outstanding as of March 31, 2014	294,671		$	12.13		2.04	$	9.2
	Options exercisable as of March 31, 2014	294,671		$	12.13		2.04	$	9.2
	(a)	Amount represents the difference between the exercise price and the market price of the Company’s stock on the last trading day of the corresponding period, multiplied by the number of in-the-money options.
Summary of Employee Stock Purchase Plan Activity	'
		Three Months Ended March 31,
	Activity, employee stock purchase plan:	2014			2013
	Cash proceeds (in millions)	$	0.8		$	0.9
	Common shares issued	26,968			67,556
	Weighted average price per share	$	27.81		$	13.19
	Weighted average grant date fair value per share	$	6.59		$	5
Summary of Stock-Based Compensation Expense And Related Tax Benefits	'
	Details of stock based compensation expense, which is included within general and administrative expense in the condensed unaudited consolidated statement of operations, and related tax benefits for the periods indicated are as follows (in millions):
		Three Months Ended March 31,
		2014			2013
	Stock-based compensation expense	$	3.3		$	2.4
	Income Tax Effects:
	Income tax benefit from stock-based compensation	$	4.5		$	1.5
	Excess tax benefit from stock-based compensation (a)	$	3.2		$	0.9
	(a)	Excess tax benefits, which represent cash flows from tax deductions in excess of the recorded tax effect of compensation expense recognized for stock options exercised and vested restricted shares, are classified as financing cash flows in the Company’s condensed unaudited consolidated statements of cash flows.

Other_Retirement_Plans_Tables

Other Retirement Plans (Tables)	3 Months Ended
	Mar. 31, 2014
Multiemployer Plans [Abstract]	'
Schedule of Multi-Employer Plan Contribution Details	'
	Total contributions to multi-employer plans, and the related number of employees covered by these plans, for the periods indicated ranged as follows:
		Multi-Employer Plans
		Covered Employees		Contributions (in millions)
	For the Three Months Ended March 31,	Low	High	Pension		Post-Retirement Benefit		Total
	2014	1,098	1,308	$	7.8	$	0.5	$	8.3
	2013	778	1,149	$	8.3	$	0.8	$	9.1

Equity_Tables

Equity (Tables)	3 Months Ended
	Mar. 31, 2014
Equity [Abstract]	'
Schedule of Share Activity	'
	The following is a summary of share activity for the period indicated:
	Share Activity (in thousands):	Common Shares			Treasury
		Outstanding			Shares
	Balance as of December 31, 2013	77,258			9,467
	Shares issued for stock option exercises	201
	Shares issued for restricted stock awards	141
	Other shares issued, net of shares withheld for taxes	(73	)
	Balance as of March 31, 2014	77,527			9,467
Schedule of Changes in Accumulated Other Comprehensive Loss	'
	Changes in accumulated other comprehensive loss by component during the periods indicated are as follows (in thousands):
			For the Three Months Ended March 31,
			2014									2013
			Unrealized (Losses) Gains
			Foreign Currency			Available-for-Sale Securities			Total			Foreign Currency			Available-for-Sale Securities			Total
	Balance as of January 1		$	(7,998	)	$	(5,288	)	$	(13,286	)	$	(105	)	$	(5,396	)	$	(5,501	)
	Activity before reclassifications, net of tax		(5,335		)	—			(5,335		)	(824		)	221			(603		)
	Reclassifications, net of tax		—			—			—			—			—			—
	Activity, net of tax		(5,335		)	—			(5,335		)	(824		)	221			(603		)
	Balance as of March 31		$	(13,333	)	$	(5,288	)	$	(18,621	)	$	(929	)	$	(5,175	)	$	(6,104	)

Segments_and_Related_Informati1

Segments and Related Information (Tables)	3 Months Ended
	Mar. 31, 2014
Segment Reporting [Abstract]	'
Schedule of Segment Reporting Information, by Segment	'
	Summarized financial information for MasTec’s reportable segments is presented and reconciled to consolidated continuing operations financial information for total MasTec in the following tables (in millions):
		For the Three Months Ended March 31,
	Revenue:	2014			2013
	Communications	$	447.1		$	424.9
	Oil and Gas	379.8			318.8
	Electrical Transmission	80.1			84.6
	Power Generation and Industrial	54.2			88.9
	Other	2.8			2.3
	Eliminations	0			(0.9		)
	Consolidated revenue	$	964		$	918.6
	Revenue generated by utilities customers represented 7.0% and 8.3% of Communications segment revenue for the three month periods ended March 31, 2014 and 2013, respectively.
		For the Three Months Ended March 31,
	EBITDA:	2014			2013
	Communications	$	43.4		$	46.4
	Oil and Gas	34.9			42.4
	Electrical Transmission	3.5			3.4
	Power Generation and Industrial	0.5			(0.2		)
	Other	0.2			0.1
	Corporate	(10.9		)	(18.6		)
	Consolidated EBITDA	$	71.6		$	73.5
		For the Three Months Ended March 31,
	Depreciation and Amortization:	2014			2013
	Communications	$	9.9		$	8.2
	Oil and Gas	18.1			18.7
	Electrical Transmission	2.8			2.3
	Power Generation and Industrial	1.5			1.7
	Corporate	1.2			0.9
	Consolidated Depreciation and Amortization	$	33.5		$	31.8
Reconciliation of EBITDA to Consolidated Income from Continuing Operations	'
	The following table presents a reconciliation of EBITDA to consolidated income from continuing operations before income taxes (in millions):
		For the Three Months Ended March 31,
	EBITDA Reconciliation:	2014			2013
	EBITDA	$	71.6		$	73.5
	Less:
	Interest expense, net	(12.0		)	(10.0		)
	Depreciation and amortization	(33.5		)	(31.8		)
	Income from continuing operations before income taxes	$	26.1		$	31.7
Schedule of Significant Customers, Revenue Concentration	'
	Revenue concentration information for significant customers as a percent of total consolidated revenue was as follows:
		For the Three Months Ended March 31,
		2014		2013
	Customer:
	AT&T	22%		18%
	DIRECTV®	14%		16%
	Enbridge, Inc.	14%		12%
	The Company's relationship with AT&T is based upon master service agreements, other service agreements and construction/installation contracts for AT&T's wireless, wireline and home security and automation businesses. Revenue from AT&T is included in the Communications segment. The Company's relationship with DIRECTV® is based upon an agreement to provide installation and maintenance services for DIRECTV®. Revenue from DIRECTV® is included in the Communications segment. The Company's relationship with Enbridge, Inc. is based upon various construction contracts for natural gas pipelines. Revenue from Enbridge, Inc. is included in the Oil and Gas segment.

Supplemental_Guarantor_Condens1

Supplemental Guarantor Condensed Unaudited Consolidating Financial Information (Tables)	3 Months Ended
	Mar. 31, 2014
Condensed Unaudited Financial Statements, Supplemental Guarantor Information [Abstract]	'
Condensed Unaudited Consolidating Statements Of Operations And Comprehensive Income	'
	CONDENSED UNAUDITED CONSOLIDATING STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME (in millions)
	For the Three Months Ended March 31, 2014	MasTec, Inc.			Guarantor			Non-Guarantor			Eliminations			Consolidated
					Subsidiaries			Subsidiaries						MasTec, Inc.
	Revenue	$	—		$	793.1		$	170.9		$	—		$	964
	Costs of revenue, excluding depreciation and amortization	—			689.8			151.3			—			841.1
	Depreciation and amortization	—			27.4			6.1			—			33.5
	General and administrative expenses	0.6			47.3			5.4			—			53.3
	Interest expense, net	—			11.7			0.3			—			12
	Other (income) expense, net	—			(2.1		)	0.1			—			(2.0		)
	(Loss) income from continuing operations before income taxes	$	(0.6	)	$	19		$	7.7		$	—		$	26.1
	Benefit from (provision for) income taxes	0.2			(9.4		)	(0.7		)	—			(9.9		)
	Net (loss) income from continuing operations	$	(0.4	)	$	9.6		$	7		$	—		$	16.2
	Net loss from discontinued operations	—			—			(0.1		)	—			(0.1		)
	Equity in income from subsidiaries, net of tax	16.4			—			—			(16.4		)	—
	Net income (loss)	$	16		$	9.6		$	6.9		$	(16.4	)	$	16.1
	Net income attributable to non-controlling interests	—			—			0.1			—			0.1
	Net income (loss) attributable to MasTec, Inc.	$	16		$	9.6		$	6.8		$	(16.4	)	$	16
	Comprehensive income (loss)	$	10.6		$	9.5		$	1.6		$	(11.0	)	$	10.7
	For the Three Months Ended March 31, 2013	MasTec, Inc.			Guarantor			Non-Guarantor			Eliminations			Consolidated
					Subsidiaries			Subsidiaries						MasTec, Inc.
	Revenue	$	—		$	843.1		$	77.2		$	(1.7	)	$	918.6
	Costs of revenue, excluding depreciation and amortization	—			721.2			72			(1.7		)	791.5
	Depreciation and amortization	—			28.9			2.9			—			31.8
	General and administrative expenses	0.3			45.1			3.5			—			48.9
	Interest expense, net	—			10			—			—			10
	Loss on extinguishment of debt	—			5.6			—			—			5.6
	Other income, net	—			(0.9		)	—			—			(0.9		)
	(Loss) income from continuing operations before income taxes	$	(0.3	)	$	33.2		$	(1.2	)	$	—		$	31.7
	Benefit from (provision for) income taxes	0.1			(13.0		)	0.5			—			(12.4		)
	Net (loss) income from continuing operations	$	(0.2	)	$	20.2		$	(0.7	)	$	—		$	19.3
	Net loss from discontinued operations	—			—			(0.9		)	—			(0.9		)
	Equity in income from subsidiaries, net of tax	18.8			—			—			(18.8		)	—
	Net income (loss)	$	18.6		$	20.2		$	(1.6	)	$	(18.8	)	$	18.4
	Net income attributable to non-controlling interests	—			—			0			—			0
	Net income (loss) attributable to MasTec, Inc.	$	18.6		$	20.2		$	(1.6	)	$	(18.8	)	$	18.4
	Comprehensive income (loss)	$	17.8		$	20.5		$	(2.5	)	$	(18.0	)	$	17.8
Condensed Unaudited Consolidating Balance Sheets	'
	CONDENSED UNAUDITED CONSOLIDATING BALANCE SHEETS (in millions)
	As of March 31, 2014	MasTec, Inc.			Guarantor			Non-Guarantor			Eliminations			Consolidated
					Subsidiaries			Subsidiaries						MasTec, Inc.
	Assets
	Current assets, including discontinued operations	$	—		$	1,165.30		$	192.6		$	—		$	1,357.90
	Property and equipment, net	—			435.9			73.7			—			509.6
	Goodwill and other intangible assets, net	—			931.8			152.7			—			1,084.50
	Net investments in and advances to (from) consolidated affiliates	1,022.50			173.9			(25.0		)	(1,171.4		)	—
	Other long-term assets, including discontinued operations	9.3			36.9			15.2			—			61.4
	Total assets	$	1,031.80		$	2,743.80		$	409.2		$	(1,171.4	)	$	3,013.40
	Liabilities and Equity
	Total current liabilities	$	—		$	735.7		$	84.7		$	—		$	820.4
	Long-term debt	—			833.3			8			—			841.3
	Other liabilities	—			236.7			78.2			—			314.9
	Total liabilities	$	—		$	1,805.70		$	170.9		$	—		$	1,976.60
	Total equity	$	1,031.80		$	938.1		$	238.3		$	(1,171.4	)	$	1,036.80
	Total liabilities and equity	$	1,031.80		$	2,743.80		$	409.2		$	(1,171.4	)	$	3,013.40
	As of December 31, 2013	MasTec, Inc.			Guarantor			Non-Guarantor			Eliminations			Consolidated
					Subsidiaries			Subsidiaries						MasTec, Inc.
	Assets
	Current assets, including discontinued operations	$	—		$	1,155.90		$	150.3		$	—		$	1,306.20
	Property and equipment, net	—			420.2			67.9			—			488.1
	Goodwill and other intangible assets, net	—			933.9			132.2			—			1,066.10
	Net investments in and advances to (from) consolidated affiliates	1,006.80			172.4			(24.1		)	(1,155.1		)	—
	Other long-term assets, including discontinued operations	9.3			36.2			15.1			—			60.6
	Total assets	$	1,016.10		$	2,718.60		$	341.4		$	(1,155.1	)	$	2,921.00
	Liabilities and Equity
	Total current liabilities	$	—		$	773.3		$	53.4		$	—		$	826.7
	Long-term debt	—			760.9			4.5			—			765.4
	Other liabilities	—			236.7			71.1			—			307.8
	Total liabilities	$	—		$	1,770.90		$	129		$	—		$	1,899.90
	Total equity	$	1,016.10		$	947.7		$	212.4		$	(1,155.1	)	$	1,021.10
	Total liabilities and equity	$	1,016.10		$	2,718.60		$	341.4		$	(1,155.1	)	$	2,921.00
Condensed Unaudited Consolidating Statements Of Cash Flows	'
	CONDENSED UNAUDITED CONSOLIDATING STATEMENTS OF CASH FLOWS (in millions)
	For the Three Months Ended March 31, 2014	MasTec, Inc.			Guarantor			Non-Guarantor			Eliminations			Consolidated
					Subsidiaries			Subsidiaries						MasTec, Inc.
	Net cash (used in) provided by operating activities	$	(0.3	)	$	15.2		$	(35.3	)	$	—		$	(20.4	)
	Cash flows (used in) provided by investing activities:
	Cash paid for acquisitions, net of cash acquired	—			(23.8		)	—			—			(23.8		)
	Capital expenditures	—			(32.6		)	(3.0		)	—			(35.6		)
	Proceeds from sale of property and equipment	—			3.4			—			—			3.4
	Payments for other investments	—			(1.1		)	—			—			(1.1		)
	Net cash used in investing activities	$	—		$	(54.1	)	$	(3.0	)	$	—		$	(57.1	)
	Cash flows provided by (used in) financing activities:
	Proceeds from (repayments of) credit facility	—			76.5			—			—			76.5
	Repayments of other borrowings and capital lease obligations	—			(12.9		)	(0.9		)	—			(13.8		)
	Excess tax benefits and net proceeds from stock-based awards	1.1			0.7			—			—			1.8
	Payments of financing costs	—			(0.2		)	—			—			(0.2		)
	Net financing activities and advances (to) from consolidated affiliates	(0.8		)	(24.7		)	25.5			—			—
	Net cash provided by financing activities	$	0.3		$	39.4		$	24.6		$	—		$	64.3
	Net increase (decrease) in cash and cash equivalents	—			0.5			(13.7		)	—			(13.2		)
	Net effect of currency translation on cash	—			—			(0.5		)	—			(0.5		)
	Cash and cash equivalents - beginning of period	—			5.3			17.7			—			23
	Cash and cash equivalents - end of period	$	—		$	5.8		$	3.5		$	—		$	9.3
	Cash and cash equivalents of discontinued operations	$	—		$	—		$	—		$	—		$	—
	Cash and cash equivalents of continuing operations	$	—		$	5.8		$	3.5		$	—		$	9.3
	For the Three Months Ended March 31, 2013	MasTec, Inc.			Guarantor			Non-Guarantor			Eliminations			Consolidated
					Subsidiaries			Subsidiaries						MasTec, Inc.
	Net cash (used in) provided by operating activities	$	(0.6	)	$	50.3		$	(23.6	)	$	—		$	26.1
	Cash flows (used in) provided by investing activities:
	Cash paid for acquisitions, net of cash acquired	—			(4.7		)	—			—			(4.7		)
	Capital expenditures	—			(25.4		)	(0.4		)	—			(25.8		)
	Proceeds from sale of property and equipment	—			3.4			—			—			3.4
	Net cash used in investing activities	$	—		$	(26.7	)	$	(0.4	)	$	—		$	(27.1	)
	Cash flows provided by (used in) financing activities:
	(Repayments of) proceeds from credit facility	$	—		$	(134.0	)	$	—		$	—		$	(134.0	)
	Proceeds from senior notes, net	—			250			—			—			250
	Repayments of other borrowings and capital lease obligations	—			(19.1		)	—			—			(19.1		)
	Excess tax benefits and net proceeds from stock-based awards	2.8			0.7			—			—			3.5
	Payments of acquisition-related contingent consideration	—			(5.0		)	—			—			(5.0		)
	Payments of financing costs, including call premiums on extinguishment of debt	—			(11.0		)	—			—			(11.0		)
	Net financing activities and advances (to) from consolidated affiliates	(2.2		)	(12.9		)	15.1			—			—
	Net cash provided by financing activities	$	0.6		$	68.7		$	15.1		$	—		$	84.4
	Net increase (decrease) in cash and cash equivalents	—			92.3			(8.9		)	—			83.4
	Net effect of currency translation on cash	—			(0.1		)	—			—			(0.1		)
	Cash and cash equivalents - beginning of period	—			12.7			14.1			—			26.8
	Cash and cash equivalents - end of period	$	—		$	104.9		$	5.2		$	—		$	110.1
	Cash and cash equivalents of discontinued operations	$	—		$	—		$	0.9		$	—		$	0.9
	Cash and cash equivalents of continuing operations	$	—		$	104.9		$	4.3		$	—		$	109.2

Business_Basis_of_Presentation2

Business, Basis of Presentation and Significant Accounting Policies (Narrative) (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
	segment
Organization, Consolidation and Presentation of Financial Statements [Abstract]	'	'
Number of reportable segments	5	'
Revenue Recognition [Line Items]	'	'
Unapproved change orders, amount	$163	$79
Unapproved change orders, description	'The Company may incur costs subject to change orders, whether approved or unapproved by the customer, and/or claims related to certain contracts. Management determines the probability that such costs will be recovered based upon evidence such as engineering studies and legal opinions, past practices with the customer, specific discussions, correspondence or preliminary negotiations with the customer. The Company treats project costs as a cost of contract performance in the period incurred if it is not probable that the costs will be recovered, or defers costs and/or recognizes revenue up to the amount of the related cost if it is probable that the contract price will be adjusted and can be reliably estimated. As of MarchB 31, 2014 and DecemberB 31, 2013, the Company had approximately $163 million and $79 million, respectively, of change orders and/or claims that had been included as contract price adjustments on certain contracts that were in the process of being negotiated in the normal course of business, including arbitration and other proceedings. These contract price adjustments represent management's best estimate of additional contract revenues that have been earned and that management believes are probable of collection. The amounts ultimately realized upon final acceptance by its customers could be higher or lower than such estimated amounts, which are primarily expected to be billed and collected within one year. The $84 million increase in change orders and/or claims since December 31, 2013 is primarily due to a project in our Oil and Gas segment, which amounts have been approved in principle subsequent to March 31, 2014.	'
New Accounting Pronouncements and Changes in Accounting Principles [Abstract]	'	'
Accounting Standards Not Yet Adopted	'In April 2014, the Financial Accounting Standards Board (bFASBb) issued Accounting Standards Update (bASUb) 2014-08, Presentation of Financial Statements (Topic 205) and Property, Plant, and Equipment (Topic 360): Reporting Discontinued Operations and Disclosures of Disposals of Components of an Entity (bASU 2014-08b). ASU 2014-08 changes the requirements for reporting discontinued operations and requires additional disclosures about discontinued operations. Only disposals of components of an entity representing a strategic shift that has, or will have, a major effect on an entitybs operations and financial results should be reported as discontinued operations under ASU 2014-08. Examples include a disposal of a major geographical area, a major line of business, or a major equity method investment. ASU 2014-08 also requires expanded disclosures about discontinued operations and requires disclosures about individually significant dispositions that do not qualify as discontinued operations. ASU 2014-08 is effective prospectively for fiscal years, and interim periods within those years, beginning after December 15, 2014. Early adoption is permitted only for disposals that have not been previously reported. The Company is currently evaluating the potential impact of this ASU on its condensed unaudited consolidated financial statements.	'
Recently Adopted Accounting Pronouncements	'In July 2013, the FASB issued ASU 2013-11, Income Taxes (Topic 740): Presentation of an Unrecognized Tax Benefit When a Net Operating Loss Carryforward, a Similar Tax Loss, or a Tax Credit Carryforward Exists (a consensus of the FASB Emerging Issues Task Force) (bASU 2013-11b).B ASU 2013-11 provides guidance on the presentation in the financial statements of an unrecognized tax benefit, or a portion of an unrecognized tax benefit, and explains that unrecognized tax benefits should be presented as a reduction to deferred tax assets for net operating loss carryforwards, similar tax losses or tax credit carryforwards. To the extent a net operating loss carryforward, similar tax loss or tax credit carryforward is not available as of the reporting date under the tax law of the applicable jurisdiction, or the tax law of the applicable jurisdiction does not require the entity to use, and the entity does not intend to use, the deferred tax asset for such purpose, the unrecognized tax benefit should be presented in the financial statements as a liability and should not be combined with deferred tax assets. ASU 2013-11 applies to all entities that have unrecognized tax benefits when a net operating loss carryforward, similar tax loss, or tax credit carryforward exists as of the reporting date. ASU 2013-11 is effective prospectively for fiscal years, and interim periods within those years, beginning after December 15, 2013. Retrospective application is permitted. The Company adopted ASU 2013-11 as of January 1, 2014. The adoption of this ASU did not have a material impact on the condensed unaudited consolidated financial statements.	'
Unapproved Change Orders [Member]	'	'
Revenue Recognition [Line Items]	'	'
Unapproved change orders, increase	$84	'
Unapproved Change Orders [Member] | Unbilled Revenue [Member]	'	'
Revenue Recognition [Line Items]	'	'
Unapproved change orders, period expected to be outstanding	'1 year	'

Earnings_Per_Share_Narrative_D

Earnings Per Share (Narrative) (Details) (USD $)	3 Months Ended
In Millions, except Share data, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Earnings Per Share [Line Items]	'	'
Computation of earnings per share, methodology	'Basic earnings per share is computed by dividing earnings available to MasTecbs common shareholders by the weighted average number of common shares outstanding for the period. Diluted earnings per share is computed by dividing earnings by the number of fully diluted shares, which includes the effect of dilutive potential issuances of common shares as determined using earnings from continuing operations. The potential issuance of common shares upon the exercise, conversion or vesting of outstanding stock options and unvested restricted share awards, as calculated under the treasury stock method, as well as shares associated with the Companybs outstanding convertible debt securities, may be dilutive.	'
Anti-dilutive common stock equivalents, shares	61,226	0
Convertible Debt [Member] | 2011 Convertible Notes [Member]	'	'
Earnings Per Share [Line Items]	'	'
Computation of earnings per share, methodology	'Due to the optional cash settlement feature of the 2011 Convertible Notes and the Company's intent to settle the principal amount of such notes in cash, the conversion shares underlying the outstanding principal amount of the 2011 Convertible Notes, totaling approximately 13.0 million shares, are not required to be included in the Company's diluted share count. If, however, the average price per share of the Company's common stock exceeds the respective conversion prices of the 2011 Convertible Notes, then the resulting premium is translated into shares, referred to as bpremium shares,b the number of which is required to be included in the Company's diluted share count. The number of premium shares included in our diluted share count varies with fluctuations in our share price. Higher share prices result in a greater number of premium shares. The Companybs weighted average share price for the three month periods ended March 31, 2014 and 2013 exceeded the conversion prices of the 2011 Convertible Notes, and as a result, dilutive premium shares have been included in the Company's share count for the corresponding periods.	'
Number of conversion shares, principal amount	13,000,000	'
Convertible Debt [Member] | 2009 Convertible Notes [Member]	'	'
Earnings Per Share [Line Items]	'	'
Computation of earnings per share, methodology	'Dilutive shares associated with the 2009 Convertible Notes are attributable to the underlying principal amounts. The number of common shares issuable upon conversion of the Companybs 2009 Convertible Notes is reflected in the calculation of weighted average diluted earnings per share for the corresponding periods by application of the bif-convertedb method to the extent its effect on the computation of earnings per share from continuing operations is dilutive. Under the bif-convertedb method, net income from continuing operations is adjusted to add back the after-tax amount of interest recognized for the period associated with the convertible notes, and correspondingly, the convertible notes are assumed to have been converted with the resulting common shares added to the number of weighted average shares outstanding.	'
Convertible Debt [Member] | 2011 4.0% Notes [Member]	'	'
Earnings Per Share [Line Items]	'	'
Number of conversion shares, principal amount	6,683,000	6,683,000
Convertible Debt [Member] | 2011 4.25% Notes [Member]	'	'
Earnings Per Share [Line Items]	'	'
Number of conversion shares, principal amount	6,268,000	6,268,000
Unsecured Debt [Member] | Convertible Debt [Member] | Total Convertible Debt [Member]	'	'
Earnings Per Share [Line Items]	'	'
Principal amount	215	'
Unsecured Debt [Member] | Convertible Debt [Member] | 2011 Convertible Notes [Member]	'	'
Earnings Per Share [Line Items]	'	'
Principal amount	202.3	'
Unsecured Debt [Member] | Convertible Debt [Member] | 2009 Convertible Notes [Member]	'	'
Earnings Per Share [Line Items]	'	'
Principal amount	12.6	'
Unsecured Debt [Member] | Convertible Debt [Member] | 2011 4.0% Notes [Member]	'	'
Earnings Per Share [Line Items]	'	'
Principal amount	105.3	'
Debt instrument, interest rate	4.00%	'
Conversion price per share	15.76	'
Unsecured Debt [Member] | Convertible Debt [Member] | 2011 4.25% Notes [Member]	'	'
Earnings Per Share [Line Items]	'	'
Principal amount	97	'
Debt instrument, interest rate	4.25%	'
Conversion price per share	15.48	'

Earnings_Per_Share_Schedule_Of

Earnings Per Share (Schedule Of Earnings Per Share Information) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2014		Mar. 31, 2013
Net income attributable to MasTec:	'		'
Net income, continuing operations - basic	$16,145	[1]	$19,317	[1]
Net loss from discontinued operations - basic and diluted	-122	[1]	-947	[1]
Net income attributable to MasTec - diluted	16,101		18,447
Weighted average shares outstanding:	'		'
Weighted average shares outstanding - basic	77,345		76,608
Dilutive common stock equivalents	850		785
Weighted average shares outstanding - diluted	86,622		84,094
Continuing Operations [Member]	'		'
Net income attributable to MasTec:	'		'
Net income attributable to MasTec - diluted	16,223		19,394
Convertible Debt [Member] | 2009 Convertible Notes [Member]	'		'
Net income attributable to MasTec:	'		'
Interest expense, net of tax, 2009 Convertible Notes	$78		$77
Weighted average shares outstanding:	'		'
Dilutive shares, 2009 Convertible Notes	806		806
Convertible Debt [Member] | 2011 Convertible Notes [Member]	'		'
Weighted average shares outstanding:	'		'
Dilutive premium shares, 2011 Convertible Notes	7,621		5,895
[1]	Calculated as total net income less amounts attributable to non-controlling interests.

Earnings_Per_Share_Schedule_Of1

Earnings Per Share (Schedule Of Convertible Note Premium Share Information) (Details) (Convertible Debt [Member], USD $)	3 Months Ended
In Thousands, except Per Share data, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
2011 4.0% Notes [Member]	'	'
Earnings Per Share [Line Items]	'	'
Number of conversion shares, principal amount	6,683	6,683
Weighted average premium value	$148,360	$86,316
Weighted average equivalent premium shares	3,909	3,010
2011 4.0% Notes [Member] | Weighted Average [Member]	'	'
Earnings Per Share [Line Items]	'	'
Weighted average actual per share price	$37.96	$28.68
2011 4.25% Notes [Member]	'	'
Earnings Per Share [Line Items]	'	'
Number of conversion shares, principal amount	6,268	6,268
Weighted average premium value	$140,925	$82,735
Weighted average equivalent premium shares	3,712	2,885
2011 4.25% Notes [Member] | Weighted Average [Member]	'	'
Earnings Per Share [Line Items]	'	'
Weighted average actual per share price	$37.96	$28.68

Acquisitions_Narrative_Details

Acquisitions (Narrative) (Details) (USD $)	3 Months Ended					0 Months Ended	3 Months Ended	0 Months Ended	3 Months Ended		3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2014	Jan. 02, 2014	Mar. 31, 2014	Jan. 02, 2014	Mar. 31, 2014	2-May-13	Mar. 31, 2014
			Earn-out Arrangements [Member]	Earn-out Arrangements [Member]	2014 and 2013 Acquisitions [Member]	2014 Acquisitions [Member]	2014 Acquisitions [Member]	2014 Acquisitions [Member]	Big Country [Member]	Big Country [Member]	Other 2013 Acquisitions [Member]
								Earn-out Arrangements [Member]
Business Acquisition [Line Items]	'	'	'	'	'	'	'	'	'	'	'
Business combination, provisional information, initial accounting incomplete, items	'	'	'	'	' As of March 31, 2014, the allocations of purchase price to the fair values of tangible and intangible assets and liabilities, including the estimated values of contingent earn-out obligations and the estimated useful lives of acquired assets for these acquisitions are provisional and remain preliminary. Management continues to assess the valuation of these items and any ultimate purchase price adjustments that may result based on the final net assets and net working capital of the acquired businesses, as prescribed in the corresponding purchase agreements.	'	'	'	'	'	'
Business combination, provisional information, initial accounting incomplete, reasons	'The Company will revise its preliminary allocations for acquired businesses if new information is obtained about the facts and circumstances existing as of the date of acquisition, or for purchase price adjustments based on the final net assets and net working capital of the acquired businesses, as prescribed in the applicable purchase agreement.	'	'	'	'	'	'	'	'	'	'
Business combination, description of acquired entity	'	'	'	'	'	'	'Effective January 1, 2014, MasTec acquired a telecommunications services firm that specializes in the engineering, installation, furnishing and integration of telecommunications equipment for an aggregate purchase price composed of approximately $23.8 million in cash and a five year earn-out, valued at $8.7 million as of the date of acquisition. This company is included in MasTec's Communications segment.	'	'Big Country is a North American oil and gas pipeline and facility construction services company, headquartered in Calgary, Alberta, Canada.	'	'Effective AprilB 1, 2013, MasTec acquired a former subcontractor to its wireless business, which provides self-perform communications tower construction, installation, maintenance and other services in support of telecommunications infrastructure construction in the Company's Communications segment. In addition, effective AugustB 1, 2013, MasTec acquired an electrical transmission services company, which focuses primarily on substation construction activities and is included within the Company's Electrical Transmission segment.
Acquisition payments in cash	'	'	'	'	'	$23,800,000	'	'	'	'	'
Estimated fair value of contingent consideration	'	'	8,700,000	0	'	'	'	8,700,000	'	'	'
Earn-out period	'	'	'	'	'	'	'	'5 years	'	'	'
Effective date of acquisition	'	'	'	'	'	'	'	'	1-May-13	'	'
Business combination, percentage of voting interests acquired	'	'	'	'	'	'	'	'	'	100.00%	'
Business combination, name of acquired entity	'	'	'	'	'	'	'	'	'Big Country Energy Services, Inc. and its affiliated operating companies (collectively, "Big Country").	'	'
Business combination, acquisition costs	$200,000	$400,000	'	'	'	'	'	'	'	'	'

Acquisitions_Schedule_of_Measu

Acquisitions (Schedule of Measurement Period Adjustments) (Details) (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Measurement Period Adjustments [Line Items]	'	'
Current assets	$1,357,936	$1,306,223
Goodwill	912,885	900,454
Current liabilties	820,389	826,746
Long-term deferred tax liabilities, net	154,151	155,012
As Previously Reported [Member]	'	'
Measurement Period Adjustments [Line Items]	'	'
Current assets	'	1,306,000
Goodwill	'	899,400
Current liabilties	'	825,500
Long-term deferred tax liabilities, net	'	154,900
Adjustments [Member] | Measurement Period Adjustments [Member] | 2013 Acquisitions [Member]	'	'
Measurement Period Adjustments [Line Items]	'	'
Current assets	'	200
Goodwill	'	1,100
Current liabilties	'	1,200
Long-term deferred tax liabilities, net	'	$100

Acquisitions_Schedule_of_Busin

Acquisitions (Schedule of Business Acquisition Pro Forma Information) (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Business Acquisition, Pro Forma Information [Abstract]	'	'
Business acquisitions, pro forma information, description	'The unaudited supplemental pro forma financial information presented below has been prepared by adjusting the historical results of MasTec to include the historical results of the acquired businesses described above. The unaudited supplemental pro forma combined historical results were then adjusted (i) to remove one-time acquisition costs; (ii) to increase amortization expense resulting from the incremental intangible assets acquired in such acquisitions; (iii) to increase interest expense as a result of the cash consideration paid; and (iv) to reduce interest expense from the repayment of acquired debt. The unaudited supplemental pro forma financial information does not include any adjustments to reflect the impact of cost savings or other synergies that may result from these acquisitions. As noted above, the unaudited supplemental pro forma financial information does not purport to be indicative of the actual results that would have been achieved by the combined companies for the periods presented or that may be achieved by the combined companies in the future.	'
Business acquisitions, pro forma revenue	$964	$1,029.10
Business acquisitions, pro forma net income from continuing operations	16.2	24.1
Aquiree revenue, year over year incremental impact	119.8	43.1
Acquiree net income from continuing operations, year over year incremental impact	$1	$1.80

Discontinued_Operations_Narrat

Discontinued Operations (Narrative) (Details) (Globetec [Member], USD $)	0 Months Ended	3 Months Ended		0 Months Ended
In Millions, unless otherwise specified	Aug. 31, 2013	Mar. 31, 2014	Mar. 31, 2014	Mar. 31, 2014
			Surety Bond [Member]	Surety Bond [Member]
				Plan [Member]
Discontinued Operations Disclosures [Line Items]	'	'	'	'
Discontinued operations description	'	'In 2012, the Company's board of directors approved a plan of sale for its Globetec business. Accordingly, Globetec's projects and assets are reflected as assets and liabilities of discontinued operations in the condensed unaudited consolidated balance sheets for all periods presented, and Globetec's results of operations are presented as discontinued operations in the condensed unaudited consolidated statements of operations for all periods presented. Effective AugustB 31, 2013, the Company sold all of its membership interests in Globetec for nominal consideration and retained certain contingent assets and liabilities.	'	'
Disposal date	'	31-Aug-13	'	'
Discontinued operation, membership interests remaining	0.00%	'	'	'
Outstanding bonds, amount	'	'	$15.90	'
Estimated cost to complete bonded projects	'	'	'	$0.50

Discontinued_Operations_Summar

Discontinued Operations (Summary of Assets and Liabilities) (Details) (Globetec [Member], USD $)	Mar. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Globetec [Member]	'	'
Discontinued Operations Disclosures [Line Items]	'	'
Current assets	$3.40	$2.30
Long-term assets	10.1	10.1
Assets of discontinued operations	13.5	12.4
Current liabilities of discontinued operations	$1.30	$1.20

Discontinued_Operations_Result

Discontinued Operations (Results of Operations from Discontinued Operations) (Details) (USD $)	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Discontinued Operations Disclosures [Line Items]	'	'
Net loss from discontinued operations	($122,000)	($947,000)
Globetec [Member]	'	'
Discontinued Operations Disclosures [Line Items]	'	'
Revenue	'	6,300,000
Loss from operations, before tax	'	-1,200,000
Benefit from income taxes	'	300,000
Net loss from discontinued operations	'	($900,000)

Goodwill_and_Other_Intangible_2

Goodwill and Other Intangible Assets (Rollforward of Goodwill by Segment) (Details) (USD $)	3 Months Ended
	Mar. 31, 2014
Goodwill [Line Items]	'
Goodwill, beginning balance	$900,454,000
Additions from new business combinations, goodwill	14,500,000
Currency translation adjustments, goodwill	-2,100,000
Goodwill, ending balance	912,885,000
Operating Segments [Member] | Communications [Member]	'
Goodwill [Line Items]	'
Goodwill, beginning balance	327,900,000
Additions from new business combinations, goodwill	14,500,000
Currency translation adjustments, goodwill	0
Goodwill, ending balance	342,400,000
Operating Segments [Member] | Oil and Gas [Member]	'
Goodwill [Line Items]	'
Goodwill, beginning balance	305,200,000
Additions from new business combinations, goodwill	0
Currency translation adjustments, goodwill	-2,100,000
Goodwill, ending balance	303,100,000
Operating Segments [Member] | Electrical Transmission [Member]	'
Goodwill [Line Items]	'
Goodwill, beginning balance	149,800,000
Additions from new business combinations, goodwill	0
Currency translation adjustments, goodwill	0
Goodwill, ending balance	149,800,000
Operating Segments [Member] | Power Generation and Industrial [Member]	'
Goodwill [Line Items]	'
Goodwill, beginning balance	117,600,000
Additions from new business combinations, goodwill	0
Currency translation adjustments, goodwill	0
Goodwill, ending balance	$117,600,000

Recovered_Sheet1

Goodwill And Other Intangible Assets (Rollforward of Other Intangible Assets) (Details) (USD $)	3 Months Ended
	Mar. 31, 2014		Mar. 31, 2013	Dec. 31, 2013
Other Intangible Assets [Line Items]	'		'	'
Other intangible assets, gross carrying amount	'		'	$245,100,000
Accumulated amortization, amortizing intangible assets	'		'	-79,500,000
Other Intangible Assets [Rollforward]	'		'	'
Other intangible assets, net, beginning balance	165,606,000		'	'
Additions from new business combinations, other intangible assets	12,000,000		'	'
Amortization of intangible assets	-4,600,000		-4,200,000	'
Other intangible assets, net, ending balance	171,562,000		'	'
Other Intangible Assets [Member]	'		'	'
Other Intangible Assets [Rollforward]	'		'	'
Currency translation adjustments, other intangible assets	-1,400,000		'	'
Customer Relationships and Backlog [Member]	'		'	'
Other Intangible Assets [Line Items]	'		'	'
Other intangible assets, amortizing, gross carrying amount	'		'	128,400,000
Accumulated amortization, amortizing intangible assets	'		'	-67,700,000
Other Intangible Assets [Rollforward]	'		'	'
Other intangible assets, net, amortizing, beginning balance	60,700,000		'	'
Additions from new business combinations, amortizing intangible assets	11,700,000		'	'
Amortization of intangible assets	-4,200,000		'	'
Currency translation adjustments, amortizing intangible assets	-200,000		'	'
Other intangible assets, net, amortizing, ending balance	68,000,000		'	'
Other Finite-Lived Intangible Assets [Member]	'		'	'
Other Intangible Assets [Line Items]	'		'	'
Other intangible assets, amortizing, gross carrying amount	'		'	22,500,000	[1]
Accumulated amortization, amortizing intangible assets	'		'	-11,800,000	[1]
Other Intangible Assets [Rollforward]	'		'	'
Other intangible assets, net, amortizing, beginning balance	10,700,000	[1]	'	'
Additions from new business combinations, amortizing intangible assets	300,000	[1]	'	'
Amortization of intangible assets	-400,000	[1]	'	'
Currency translation adjustments, amortizing intangible assets	-100,000	[1]	'	'
Other intangible assets, net, amortizing, ending balance	10,500,000	[1]	'	'
Trade Names [Member]	'		'	'
Other Intangible Assets [Line Items]	'		'	'
Other intangible assets, non-amortizing, gross carrying amount	34,800,000		'	'
Other Intangible Assets [Rollforward]	'		'	'
Other intangible assets, non-amortizing, beginning balance	34,800,000		'	'
Additions from new business combinations, non-amortizing intangible assets	0		'	'
Currency translation adjustments, non-amortizing intangible assets	0		'	'
Other intangible assets, non-amortizing, ending balance	34,800,000		'	'
Pre-Qualifications [Member]	'		'	'
Other Intangible Assets [Line Items]	'		'	'
Other intangible assets, non-amortizing, gross carrying amount	58,300,000		'	'
Other Intangible Assets [Rollforward]	'		'	'
Other intangible assets, non-amortizing, beginning balance	59,400,000		'	'
Additions from new business combinations, non-amortizing intangible assets	0		'	'
Currency translation adjustments, non-amortizing intangible assets	-1,100,000		'	'
Other intangible assets, non-amortizing, ending balance	$58,300,000		'	'
[1]	Consists principally of trade names and non-compete agreements.

Goodwill_and_Other_Intangible_3

Goodwill and Other Intangible Assets (Narrative) (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Goodwill and Intangible Assets Disclosure [Abstract]	'	'
Amortization of intangible assets	$4.60	$4.20

Recovered_Sheet2

Fair Value Of Financial Instruments (Schedule Of Fair Values Of Financial Assets And Liabilities Measured On A Recurring Basis) (Details) (Fair Value [Member], USD $)	Mar. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Fair Value, Assets and Liabilities Measured on Recurring and Non-Recurring Basis [Line Items]	'	'
Life insurance surrender values	$5.50	$5.30
Earn-out Arrangements [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Non-Recurring Basis [Line Items]	'	'
Acquisition-related contingent consideration	170.3	162.9
Level 1 [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Non-Recurring Basis [Line Items]	'	'
Life insurance surrender values	5.5	5.3
Level 3 [Member] | Earn-out Arrangements [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Non-Recurring Basis [Line Items]	'	'
Acquisition-related contingent consideration	$170.30	$162.90

Recovered_Sheet3

Fair Value Of Financial Instruments (Narrative) (Details) (USD $)	Mar. 31, 2014	Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2014	Dec. 31, 2013	Mar. 31, 2014	Mar. 31, 2014	Mar. 31, 2014
	Senior Notes [Member]	Earn-out Arrangements [Member]	Earn-out Arrangements [Member]	Earn-out Arrangements [Member]	Earn-out Arrangements [Member]	Level 1 [Member]	Level 1 [Member]	Level 3 [Member]
	Unsecured Debt [Member]			Foreign Currency Translation Adjustments [Member]	Foreign Currency Translation Adjustments [Member]	Senior Notes [Member]	Cash Surrender Value [Member]	Earn-out Arrangements [Member]
	4.875% Senior Notes [Member]					Unsecured Debt [Member]
						Total Senior And Senior Convertible Notes [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Non-Recurring Basis [Line Items]	'	'	'	'	'	'	'	'
Fair value measurements, valuation techniques	'	'	'	'	'	'The estimated fair values of the Companybs 4.875% Senior Notes, 2009 Convertible Notes and 2011 Convertible Notes are based on quoted market prices, a Level 1 input.	'Cash surrender values of life insurance policies are based on current cash surrender values as quoted by insurance carriers.	'The fair value of such acquisition-related contingent consideration is based on managementbs estimates and entity-specific assumptions and is evaluated on an on-going basis.
Debt instrument, interest rate	4.88%	'	'	'	'	'	'	'
Additions from new business combinations, acquisition-related contingent consideration	'	$8,700,000	$0	'	'	'	'	'
Payments of acquisition-related contingent consideration	'	0	600,000	'	'	'	'	'
Foreign currency translation adjustments included in other comprehensive income, acquisition-related contingent consideration	'	'	'	$1,400,000	$400,000	'	'	'

Fair_Value_of_Financial_Instru2

Fair Value of Financial Instruments (Schedule Of Fair Values Of Financial Assets and Liabilities Measured On A Non-Recurring Basis) (Details) (Unsecured Debt [Member], USD $)	Mar. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Carrying Amount [Member] | Senior Notes [Member] | 4.875% Senior Notes [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Non-Recurring Basis [Line Items]	'	'
Senior notes	$400	$400
Carrying Amount [Member] | Convertible Debt [Member] | 2009 Convertible Notes [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Non-Recurring Basis [Line Items]	'	'
Convertible notes	12.6	12.6
Carrying Amount [Member] | Convertible Debt [Member] | 2011 Convertible Notes [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Non-Recurring Basis [Line Items]	'	'
Convertible notes	199.7	198.3
Fair Value [Member] | Senior Notes [Member] | 4.875% Senior Notes [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Non-Recurring Basis [Line Items]	'	'
Senior notes	390.5	380
Fair Value [Member] | Convertible Debt [Member] | 2009 Convertible Notes [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Non-Recurring Basis [Line Items]	'	'
Convertible notes	35	26.6
Fair Value [Member] | Convertible Debt [Member] | 2011 Convertible Notes [Member]	'	'
Fair Value, Assets and Liabilities Measured on Recurring and Non-Recurring Basis [Line Items]	'	'
Convertible notes	$563.20	$428.30

Recovered_Sheet4

Accounts Receivable, Net Of Allowance (Schedule Of Accounts Receivable, Net of Allowance) (Details) (USD $)	Mar. 31, 2014	Dec. 31, 2013
Receivables [Abstract]	'	'
Contract billings	$627,100,000	$606,500,000
Retainage	135,600,000	159,300,000
Costs and earnings in excess of billings	448,600,000	384,600,000
Accounts receivable, gross	1,211,300,000	1,150,400,000
Less allowance for doubtful accounts	-15,700,000	-15,800,000
Accounts receivable, net	$1,195,603,000	$1,134,577,000

Debt_Schedule_of_Long_Term_Deb

Debt (Schedule of Long Term Debt Instruments) (Details) (USD $)	3 Months Ended
	Mar. 31, 2014	Dec. 31, 2013
Debt Instrument [Line Items]	'	'
Line of credit facility, expiration date	29-Oct-18	'
Capital lease obligations	$123,200,000	$126,000,000
Total debt	894,200,000	816,800,000
Less current maturities	-52,949,000	-51,376,000
Long-term debt	841,335,000	765,425,000
Revolving Credit Facility [Member]	'	'
Debt Instrument [Line Items]	'	'
Credit facility, amount outstanding	128,600,000	53,000,000
Senior Notes [Member] | 4.875% Senior Notes [Member] | Unsecured Debt [Member]	'	'
Debt Instrument [Line Items]	'	'
Debt instrument, maturity date	15-Mar-23	'
Carrying value of debt	400,000,000	400,000,000
Convertible Debt [Member] | 2011 4.0% Notes [Member] | Unsecured Debt [Member]	'	'
Debt Instrument [Line Items]	'	'
Debt instrument, maturity date	15-Jun-14	'
Carrying value of debt	104,600,000	103,800,000
Convertible Debt [Member] | 2011 4.25% Notes [Member] | Unsecured Debt [Member]	'	'
Debt Instrument [Line Items]	'	'
Debt instrument, maturity date	15-Dec-14	'
Carrying value of debt	95,100,000	94,500,000
Convertible Debt [Member] | 2009 4.0% Notes [Member] | Unsecured Debt [Member]	'	'
Debt Instrument [Line Items]	'	'
Debt instrument, maturity date	15-Jun-14	'
Carrying value of debt	9,600,000	9,600,000
Convertible Debt [Member] | 2009 4.25% Notes [Member] | Unsecured Debt [Member]	'	'
Debt Instrument [Line Items]	'	'
Debt instrument, maturity date	15-Dec-14	'
Carrying value of debt	3,000,000	3,000,000
Capital Lease Obligations [Member] | Maximum [Member]	'	'
Debt Instrument [Line Items]	'	'
Lease expiration date	30-Mar-20	'
Notes Payable [Member] | Equipment [Member]	'	'
Debt Instrument [Line Items]	'	'
Carrying value of debt	$30,100,000	$26,900,000
Notes Payable [Member] | Equipment [Member] | Maximum [Member]	'	'
Debt Instrument [Line Items]	'	'
Debt instrument, maturity date	1-May-18	'

Property_And_Equipment_Net_Sch

Property And Equipment, Net (Schedule Of Property And Equipment, Net) (Details) (USD $)	Mar. 31, 2014	Dec. 31, 2013
Property and Equipment [Line Items]	'	'
Property and equipment	$899,300,000	$863,400,000
Less accumulated depreciation and amortization	-389,700,000	-375,300,000
Property and equipment, net	509,585,000	488,132,000
Land [Member]	'	'
Property and Equipment [Line Items]	'	'
Property and equipment	4,600,000	4,800,000
Building and Leasehold Improvements [Member]	'	'
Property and Equipment [Line Items]	'	'
Property and equipment	17,600,000	18,000,000
Machinery and Equipment [Member]	'	'
Property and Equipment [Line Items]	'	'
Property and equipment	752,200,000	727,100,000
Office Furniture and Equipment [Member]	'	'
Property and Equipment [Line Items]	'	'
Property and equipment	108,000,000	102,500,000
Construction in Progress [Member]	'	'
Property and Equipment [Line Items]	'	'
Property and equipment	$16,900,000	$11,000,000

Accounts_Receivable_Net_of_All2

Accounts Receivable, Net of Allowance (Narrative) (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Receivables [Abstract]	'	'
Provision for doubtful accounts	$0.60	$3.30

Debt_Schedule_of_Long_Term_Deb1

Debt (Schedule of Long Term Debt Instruments) (Parenthetical) (Details)	Mar. 31, 2014
Senior Notes [Member] | 4.875% Senior Notes [Member] | Unsecured Debt [Member]	'
Debt Instrument [Line Items]	'
Debt instrument, interest rate	4.88%
Convertible Debt [Member] | 2011 4.0% Notes [Member] | Unsecured Debt [Member]	'
Debt Instrument [Line Items]	'
Debt instrument, interest rate	4.00%
Convertible Debt [Member] | 2011 4.25% Notes [Member] | Unsecured Debt [Member]	'
Debt Instrument [Line Items]	'
Debt instrument, interest rate	4.25%
Convertible Debt [Member] | 2009 4.0% Notes [Member] | Unsecured Debt [Member]	'
Debt Instrument [Line Items]	'
Debt instrument, interest rate	4.00%
Convertible Debt [Member] | 2009 4.25% Notes [Member] | Unsecured Debt [Member]	'
Debt Instrument [Line Items]	'
Debt instrument, interest rate	4.25%
Capital Lease Obligations [Member]	'
Debt Instrument [Line Items]	'
Debt instrument, weighted average interest rate	2.90%
Notes Payable [Member] | Equipment [Member]	'
Debt Instrument [Line Items]	'
Debt instrument, weighted average interest rate	3.00%

Property_And_Equipment_Net_Nar

Property And Equipment, Net (Narrative) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Property and Equipment [Line Items]	'	'
Depreciation and amortization	$33,494	$31,753
Property and Equipment [Member]	'	'
Property and Equipment [Line Items]	'	'
Depreciation and amortization	$28,900	$27,600

Debt_Credit_Facility_Narrative

Debt (Credit Facility) (Narrative) (Details) (USD $)	0 Months Ended		3 Months Ended
	Mar. 31, 2014	Dec. 31, 2013	Mar. 31, 2014
Debt Instrument [Line Items]	'	'	'
Line of credit facility, expiration date	'	'	29-Oct-18
Line of credit facility, maximum borrowing capacity	$750,000,000	'	$750,000,000
Letters of credit outstanding	134,700,000	134,800,000	134,700,000
Line of credit facility, remaining borrowing capacity	486,800,000	562,100,000	486,800,000
Unused credit facility fee	0.30%	0.30%	'
Revolving Credit Facility [Member]	'	'	'
Debt Instrument [Line Items]	'	'	'
Credit facility, amount outstanding	128,600,000	53,000,000	128,600,000
Revolving Credit Facility [Member] | Weighted Average [Member]	'	'	'
Debt Instrument [Line Items]	'	'	'
Line of credit facility, interest rate	2.08%	2.14%	2.08%
Letter of Credit [Member]	'	'	'
Debt Instrument [Line Items]	'	'	'
Line of credit facility, capacity available for issuance of letters of credit	315,300,000	315,200,000	315,300,000
Letter of Credit [Member] | Performance Standby [Member]	'	'	'
Debt Instrument [Line Items]	'	'	'
Line of credit facility, interest rate	0.75%	0.75%	0.75%
Letter of Credit [Member] | Financial Standby [Member]	'	'	'
Debt Instrument [Line Items]	'	'	'
Line of credit facility, interest rate	1.50%	1.50%	1.50%
Canadian Dollars [Member] | Revolving Credit Facility [Member] | Maximum [Member]	'	'	'
Debt Instrument [Line Items]	'	'	'
Line of credit facility, revolving loan sublimit	$100,000,000	'	$100,000,000

Debt_Senior_Convertible_Notes_

Debt (Senior Convertible Notes) (Narrative) (Details) (Convertible Debt [Member], Unsecured Debt [Member], USD $)	Mar. 31, 2014	Dec. 31, 2013	Mar. 31, 2014	Mar. 31, 2014	Mar. 31, 2014	Mar. 31, 2014
In Millions, unless otherwise specified	2011 Convertible Notes [Member]	2011 Convertible Notes [Member]	2011 4.0% Notes [Member]	2011 4.25% Notes [Member]	Total Convertible Debt [Member]	Total Convertible Debt [Member]
					Plan [Member]	Plan [Member]
Debt Instrument [Line Items]	'	'	'	'	'	'
Unamortized debt discount and financing costs	$2.70	$4	'	'	'	'
Debt instrument, maturity date	'	'	15-Jun-14	15-Dec-14	'	'
Debt, intent to refinance, amount	'	'	'	'	$215	'
Debt, intent to refinance, description	'	'	'	'	'	'The Company expects to refinance the $215.0 million principal amount of its senior convertible notes on a long-term basis either through its 2013 Credit Facility or through other sources of available funding and, therefore, has reflected the carrying amounts of these notes within long-term debt in the Company's condensed unaudited consolidated balance sheets.

Debt_Debt_Guarantees_and_Coven

Debt (Debt Guarantees and Covenants) (Narrative) (Details)	3 Months Ended
	Mar. 31, 2014
Debt Instrument [Line Items]	'
Debt instrument, covenant compliance	'MasTec was in compliance with all provisions and covenants pertaining to its outstanding debt instruments as of March 31, 2014 and December 31, 2013.
Guarantor Subsidiaries [Member]	'
Debt Instrument [Line Items]	'
Percentage of voting interests owned, guarantor subsidiaries	100.00%
Total Senior And Senior Convertible Notes [Member] | Senior Notes [Member] | Unsecured Debt [Member]	'
Debt Instrument [Line Items]	'
Debt instrument, guarantees	'The Companybs 4.875% Senior Notes, 2011 Convertible Notes and 2009 Convertible Notes are fully and unconditionally guaranteed on an unsecured, unsubordinated, joint and several basis by certain of the Company's existing and future 100%-owned direct and indirect domestic subsidiaries that are guarantors of the 2013 Credit Facility or other outstanding indebtedness.

Debt_Schedule_Of_Interest_Expe

Debt (Schedule Of Interest Expense, Net) (Details) (USD $)	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Interest expense:	'	'
Contractual and other interest expense	$9,700,000	$7,900,000
Accretion of senior convertible note discount	1,400,000	1,300,000
Amortization of deferred financing costs	900,000	900,000
Total interest expense	12,000,000	10,100,000
Interest income	0	-100,000
Interest expense, net	$12,003,000	$10,045,000

Lease_Obligations_Capital_Leas

Lease Obligations (Capital Lease Obligations) (Narrative) (Details) (USD $)	Mar. 31, 2014	Dec. 31, 2013
In Millions, unless otherwise specified
Leases [Abstract]	'	'
Assets held under capital lease, gross	$207.80	$199.60
Assets held under capital lease, net	$144.10	$141.30

Lease_Obligations_Operating_Le

Lease Obligations (Operating Lease Obligations) (Narrative) (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Lease Term In Excess Of One Year [Member]	'	'
Operating Leased Assets [Line Items]	'	'
Operating leases, rent expense	$15.50	$11.90
Lease Term Less Than One Year [Member]	'	'
Operating Leased Assets [Line Items]	'	'
Operating leases, rent expense	$48.40	$36.90

StockBased_Compensation_and_Ot2

Stock-Based Compensation and Other Employee Benefit Plans (Narrative) (Details) (USD $)	0 Months Ended	3 Months Ended
In Millions, except Share data, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2014	Mar. 31, 2013
Stock-Based Compensation and Other Employee Benefit Plans [Line Items]	'	'	'
Shares available for grant or issuance	6,243,047	6,243,047	'
Intrinsic value of stock options exercised	'	$6.30	$3.50
Proceeds from stock options exercised	'	0.6	1.9
Restricted Stock Plan [Member]	'	'	'
Stock-Based Compensation and Other Employee Benefit Plans [Line Items]	'	'	'
Unearned compensation	24.3	24.3	'
Unearned compensation, weighted average expected recognition period	'1 year 7 months 6 days	'	'
Intrinsic value of vested awards	'	$5.90	$0.70
Employee Stock Option Plan [Member]	'	'	'
Stock-Based Compensation and Other Employee Benefit Plans [Line Items]	'	'	'
Stock-based compensation, percentage vested	'	100.00%	'
Employee Stock Purchase Plan [Member]	'	'	'
Stock-Based Compensation and Other Employee Benefit Plans [Line Items]	'	'	'
Stock-based compensation plan, description	'	'The Company's employee stock purchase plans allow qualified employees to purchase MasTec, Inc. common stock at 85% of the fair market value of the common stock at the lower of (i) the date of commencement of the offering period or (ii) the last day of the exercise period, as defined in the plan documents.	'
Stock-based compensation, purchase price of common stock, percentage of fair value	'	85.00%	'
Stock-based compensation, fair value assumptions, method used	'	'The fair value of purchases under the Company's employee stock purchase plans is estimated using the Black-Scholes option-pricing valuation model.	'

StockBased_Compensation_and_Ot3

Stock-Based Compensation and Other Employee Benefit Plans (Summary of Restricted Share Awards) (Details) (Restricted Stock Plan [Member], USD $)	3 Months Ended
	Mar. 31, 2014
Restricted Stock Plan [Member]	'
Restricted Share Award Activity, Number of Shares [Roll Forward]	'
Non-vested restricted shares, beginning balance	1,123,545
Granted	326,442
Vested	-141,138
Canceled/forfeited	-13,450
Non-vested restricted shares, ending balance	1,295,399
Restricted Share Award Activity, Weighted Average Grant Date Fair Value [Roll Forward]	'
Weighted average grant date fair value, beginning balance	$23.78
Granted	$41.39
Vested	$19.41
Canceled/forfeited	$16.05
Weighted average grant date fair value, ending balance	$28.77

StockBased_Compensation_and_Ot4

Stock-Based Compensation and Other Employee Benefit Plans (Summary of Stock Options) (Details) (USD $)	0 Months Ended				3 Months Ended
In Millions, except Share data, unless otherwise specified	Mar. 31, 2014		Dec. 31, 2013		Mar. 31, 2014
Outstanding Stock Options, Activity [Roll Forward]	'		'		'
Options outstanding, vested, beginning balance	'		'		495,571
Exercised	'		'		-200,900
Canceled/forfeited	'		'		0
Options outstanding, vested, ending balance	294,671		495,571		294,671
Outstanding Stock Options, Weighted Average Exercise Price [Roll Forward]	'		'		'
Weighted average exercise price, vested, beginning balance	'		'		$11.17
Exercised	'		'		$9.77
Canceled/forfeited	'		'		$0
Weighted average exercise price, vested, ending balance	$12.13		$11.17		$12.13
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract]	'		'		'
Options exercisable	294,671		'		294,671
Options exercisable, weighted average exercise price	$12.13		'		$12.13
Options outstanding, vested, weighted average remaining contractual life	'2 years 0 months 15 days		'1 year 11 months 16 days		'
Options exercisable, weighted average remaining contractual life	'2 years 0 months 15 days		'		'
Options outstanding, vested, aggregate intrinsic value	$9.20	[1]	$10.70	[1]	$9.20	[1]
Options exercisable, aggregate intrinsic value	$9.20	[1]	'		$9.20	[1]
[1]	Amount represents the difference between the exercise price and the market price of the Companybs stock on the last trading day of the corresponding period, multiplied by the number of in-the-money options.

StockBased_Compensation_and_Ot5

Stock-Based Compensation and Other Employee Benefit Plans (Summary of Employee Stock Purchase Plan Activity) (Details) (USD $)	3 Months Ended
In Millions, except Share data, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Stock-Based Compensation and Other Employee Benefit Plans [Line Items]	'	'
Common shares issued	26,968	67,556
Weighted average price per share	$9.77	'
Employee Stock Purchase Plan [Member]	'	'
Stock-Based Compensation and Other Employee Benefit Plans [Line Items]	'	'
Cash proceeds (in millions)	$0.80	0.9
Weighted average price per share	$27.81	13.19
Weighted average grant date fair value per share	$6.59	5

StockBased_Compensation_and_Ot6

Stock-Based Compensation and Other Employee Benefit Plans (Summary of Stock-Based Compensation Expense and Related Tax Benefits) (Details) (USD $)	3 Months Ended
	Mar. 31, 2014		Mar. 31, 2013
Share-based Compensation [Abstract]	'		'
Stock-based compensation expense	$3,260,000		$2,357,000
Income Tax Effects:	'		'
Income tax benefit from stock-based compensation	4,500,000		1,500,000
Excess tax benefit from stock-based compensation	$3,246,000	[1]	$903,000	[1]
[1]	Excess tax benefits, which represent cash flows from tax deductions in excess of the recorded tax effect of compensation expense recognized for stock options exercised and vested restricted shares, are classified as financing cash flows in the Companybs condensed unaudited consolidated statements of cash flows.

Other_Retirement_Plans_Narrati

Other Retirement Plans (Narrative) (Details)	3 Months Ended
	Mar. 31, 2014
Multiemployer Plans [Abstract]	'
Multi-employer plans, general nature	'Certain of MasTecbs subsidiaries contribute amounts to multi-employer pension and other multi-employer benefit plans and trusts. Contributions are generally based on fixed amounts per hour per employee for employees covered under these plans. Multi-employer plan contribution rates are determined annually and assessed on a bpay-as-you-gob basis based on union employee payrolls. Union payrolls cannot be determined for future periods because the number of union employees employed at any given time, and the plans in which they may participate, vary depending upon the location and number of ongoing projects at a given time and the need for union resources in connection with those projects.

Other_Retirement_Plans_Schedul

Other Retirement Plans (Schedule of Multi-Employer Plan Contributions) (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Multi-Employer Plans [Line Items]	'	'
Multi-employer plans, contributions	$8.30	$9.10
Multi-Employer Plans, Pension [Member]	'	'
Multi-Employer Plans [Line Items]	'	'
Multi-employer plans, contributions	7.8	8.3
Multi-employer Plans, Postretirement Benefit [Member]	'	'
Multi-Employer Plans [Line Items]	'	'
Multi-employer plans, contributions	$0.50	$0.80
Workforce Subject to Collective Bargaining Arrangements [Member] | Minimum [Member]	'	'
Multi-Employer Plans [Line Items]	'	'
Multi-employer plans, covered employees	1,098	778
Workforce Subject to Collective Bargaining Arrangements [Member] | Maximum [Member]	'	'
Multi-Employer Plans [Line Items]	'	'
Multi-employer plans, covered employees	1,308	1,149

Equity_Schedule_of_Share_Activ

Equity (Schedule of Share Activity) (Details)	3 Months Ended
	Mar. 31, 2014
Rollforward of Share Activity	'
Common shares outstanding, beginning balance	77,258,000
Shares issued for stock option exercises	200,900
Shares issued for restricted stock awards	141,138
Common shares outstanding, ending balance	77,527,000
Treasury shares, beginning balance	9,467,286
Treasury shares, ending balance	9,467,286
Other Share Activity [Member]	'
Rollforward of Share Activity	'
Other shares issued, net of shares withheld for taxes	-73,000

Equity_Schedule_of_Changes_in_

Equity (Schedule of Changes in Accumulated Other Comprehensive Loss) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Accumulated Other Comprehensive Income (Loss) [Line Items]	'	'
Accumulated other comprehensive loss, beginning balance	($13,286)	($5,501)
Activity before reclassifications, net of tax	-5,335	-603
Reclassifications, net of tax	0	0
Activity, net of tax	-5,335	-603
Accumulated other comprehensive loss, ending balance	-18,621	-6,104
Foreign Currency [Member]	'	'
Accumulated Other Comprehensive Income (Loss) [Line Items]	'	'
Accumulated other comprehensive loss, beginning balance	-7,998	-105
Activity before reclassifications, net of tax	-5,335	-824
Reclassifications, net of tax	0	0
Activity, net of tax	-5,335	-824
Accumulated other comprehensive loss, ending balance	-13,333	-929
Available-for-Sale-Securities [Member]	'	'
Accumulated Other Comprehensive Income (Loss) [Line Items]	'	'
Accumulated other comprehensive loss, beginning balance	-5,288	-5,396
Activity before reclassifications, net of tax	0	221
Reclassifications, net of tax	0	0
Activity, net of tax	0	221
Accumulated other comprehensive loss, ending balance	($5,288)	($5,175)

Income_Taxes_Narrative_Details

Income Taxes (Narrative) (Details) (USD $)	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2013
Income Tax Disclosure [Abstract]	'	'	'
Effective income tax rate, continuing operations	38.00%	39.00%	'
Quarterly financial information, income taxes	'In determining the quarterly provision for income taxes, management uses an estimated annual effective tax rate based on forecasted annual pre-tax income, permanent tax differences, statutory tax rates and tax planning opportunities in the various jurisdictions in which the Company operates. The impact of significant discrete items is separately recognized in the quarter(s) in which they occur.	'	'
Current deferred tax assets, net	$12,700,000	'	$16,300,000
Long-term deferred tax liabilities, net	$154,151,000	'	$155,012,000

Segments_and_Related_Informati2

Segments and Related Information (Narrative) (Details) (USD $)	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013	Dec. 31, 2013
	segment
Segment Reporting Information [Line Items]	'	'	'
Segment reporting, factors used to identify entity's reportable segments	'MasTec presents its continuing operations in five reportable segments: (1) Communications; (2) Oil and Gas; (3) Electrical Transmission; (4) Power Generation and Industrial and (5) Other. This structure is generally focused on broad end-user markets for MasTec's labor-based construction services.	'	'
Number of reportable segments	5	'	'
Segment reporting information, description of products and services	'All five reportable segments derive their revenues from the engineering, installation and maintenance of infrastructure, primarily in North America.	'	'
Segment reporting, description of all other segments	'The Other segment primarily includes small business units that perform construction services for a variety of end markets in Mexico and elsewhere internationally.	'	'
Revenue	$964,029,000	$918,648,000	'
Property and equipment, net	509,585,000	'	488,132,000
Intangible assets and goodwill, net	1,084,500,000	'	1,066,100,000
United States [Member] | Reportable Geographical Components [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Revenue	837,900,000	878,900,000	'
Property and equipment, net	461,800,000	'	436,900,000
Intangible assets and goodwill, net	995,800,000	'	973,300,000
Foreign Operations [Member] | Reportable Geographical Components [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Revenue	126,100,000	39,700,000	'
Property and equipment, net	47,800,000	'	51,200,000
Intangible assets and goodwill, net	88,600,000	'	92,700,000
Communications [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Segment reporting information, description of products and services	'The Communications segment performs engineering, construction and maintenance of communications infrastructure primarily related to wireless and wireline communications and install to the home, and to a lesser extent, infrastructure for electrical utilities.	'	'
Communications [Member] | Operating Segments [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Revenue	447,100,000	424,900,000	'
Communications [Member] | Customer Concentration Risk [Member] | Revenue [Member] | Utilities [Member] | Operating Segments [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Utilities customers, percentage of consolidated communications revenue	7.00%	8.30%	'
Oil and Gas [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Segment reporting information, description of products and services	'MasTec performs engineering, construction and maintenance services on oil and natural gas pipelines and processing facilities for the energy and utilities industries through its Oil and Gas segment.	'	'
Oil and Gas [Member] | Operating Segments [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Revenue	379,800,000	318,800,000	'
Electrical Transmission [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Segment reporting information, description of products and services	'The Electrical Transmission segment primarily serves the energy and utility industries through the engineering, construction and maintenance of electrical transmission lines and substations.	'	'
Electrical Transmission [Member] | Operating Segments [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Revenue	80,100,000	84,600,000	'
Power Generation and Industrial [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Segment reporting information, description of products and services	'The Power Generation and Industrial segment primarily serves the energy and utility end markets and other end markets through the installation and construction of renewable power facilities, related electrical transmission infrastructure, ethanol facilities and various types of industrial infrastructure.	'	'
Power Generation and Industrial [Member] | Operating Segments [Member]	'	'	'
Segment Reporting Information [Line Items]	'	'	'
Revenue	$54,200,000	$88,900,000	'

Segments_and_Related_Informati3

Segments and Related Information (Schedule of Segment Reporting Information, by Segment - Revenue) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Segment Reporting Information [Line Items]	'	'
Revenue	$964,029	$918,648
Operating Segments [Member] | Communications [Member]	'	'
Segment Reporting Information [Line Items]	'	'
Revenue	447,100	424,900
Operating Segments [Member] | Oil and Gas [Member]	'	'
Segment Reporting Information [Line Items]	'	'
Revenue	379,800	318,800
Operating Segments [Member] | Electrical Transmission [Member]	'	'
Segment Reporting Information [Line Items]	'	'
Revenue	80,100	84,600
Operating Segments [Member] | Power Generation and Industrial [Member]	'	'
Segment Reporting Information [Line Items]	'	'
Revenue	54,200	88,900
Operating Segments [Member] | Other Segments [Member]	'	'
Segment Reporting Information [Line Items]	'	'
Revenue	2,800	2,300
Intersegment Eliminations [Member]	'	'
Segment Reporting Information [Line Items]	'	'
Revenue	$0	($900)

Segments_and_Related_Informati4

Segments and Related Information (Schedule of Segment Reporting Information, by Segment - EBITDA) (Details) (Continuing Operations [Member], USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Segment Reporting Information [Line Items]	'	'
EBITDA	$71.60	$73.50
Operating Segments [Member] | Communications [Member]	'	'
Segment Reporting Information [Line Items]	'	'
EBITDA	43.4	46.4
Operating Segments [Member] | Oil and Gas [Member]	'	'
Segment Reporting Information [Line Items]	'	'
EBITDA	34.9	42.4
Operating Segments [Member] | Electrical Transmission [Member]	'	'
Segment Reporting Information [Line Items]	'	'
EBITDA	3.5	3.4
Operating Segments [Member] | Power Generation and Industrial [Member]	'	'
Segment Reporting Information [Line Items]	'	'
EBITDA	0.5	-0.2
Operating Segments [Member] | Other Segments [Member]	'	'
Segment Reporting Information [Line Items]	'	'
EBITDA	0.2	0.1
Corporate, Non-Segment [Member]	'	'
Segment Reporting Information [Line Items]	'	'
EBITDA	($10.90)	($18.60)

Segments_and_Related_Informati5

Segments and Related Information (Schedule of Segment Reporting Information, by Segment - Depreciation and Amortization) (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2014	Mar. 31, 2013
Segment Reporting Information [Line Items]	'	'
Depreciation and amortization	$33,494	$31,753
Operating Segments [Member] | Communications [Member]	'	'
Segment Reporting Information [Line Items]	'	'
Depreciation and amortization	9,900	8,200
Operating Segments [Member] | Oil and Gas [Member]	'	'
Segment Reporting Information [Line Items]	'	'
Depreciation and amortization	18,100	18,700
Operating Segments [Member] | Electrical Transmission [Member]	'	'
Segment Reporting Information [Line Items]	'	'
Depreciation and amortization	2,800	2,300
Operating Segments [Member] | Power Generation and Industrial [Member]	'	'
Segment Reporting Information [Line Items]	'	'
Depreciation and amortization	1,500	1,700
Corporate, Non-Segment [Member]	'	'
Segment Reporting Information [Line Items]	'	'
Depreciation and amortization	$1,200	$900

Segments_and_Related_Informati6

Segments and Related Information (Reconciliation of EBITDA to Consolidated Income from Continuing Operations) (Details) (USD $)	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Less:	'	'
Interest expense, net	($12,003,000)	($10,045,000)
Depreciation and amortization	-33,494,000	-31,753,000
Income from continuing operations before income taxes	26,106,000	31,668,000
Continuing Operations [Member]	'	'
Segment Reporting Information [Line Items]	'	'
EBITDA	$71,600,000	$73,500,000

Segments_and_Related_Informati7

Segments and Related Information (Schedule of Significant Customers, Revenue Concentration Information) (Details) (Operating Segments [Member], Customer Concentration Risk [Member], Revenue [Member])	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
AT&T [Member] | Communications [Member]	'	'
Revenue, Significant Customer [Line Items]	'	'
Significant customer, percentage of consolidated revenue	22.00%	18.00%
Segment reporting, disclosure of significant customers	'The Company's relationship with AT&T is based upon master service agreements, other service agreements and construction/installation contracts for AT&T's wireless, wireline and home security and automation businesses. Revenue from AT&T is included in the Communications segment.	'
DIRECTV[Member] | Communications [Member]	'	'
Revenue, Significant Customer [Line Items]	'	'
Significant customer, percentage of consolidated revenue	14.00%	16.00%
Segment reporting, disclosure of significant customers	'The Company's relationship with DIRECTVB. is based upon an agreement to provide installation and maintenance services for DIRECTVB.. Revenue from DIRECTVB. is included in the Communications segment.	'
Enbridge [Member] | Oil and Gas [Member]	'	'
Revenue, Significant Customer [Line Items]	'	'
Significant customer, percentage of consolidated revenue	14.00%	12.00%
Segment reporting, disclosure of significant customers	'The Company's relationship with Enbridge, Inc. is based upon various construction contracts for natural gas pipelines. Revenue from Enbridge, Inc. is included in the Oil and Gas segment.	'

Commitments_and_Contingencies_

Commitments and Contingencies (Narrative) (Details) (USD $)

3 Months Ended

0 Months Ended

3 Months Ended

In Millions, unless otherwise specified

Mar. 31, 2014

Dec. 31, 2013

Mar. 31, 2014

Dec. 31, 2013

Mar. 31, 2014

Dec. 31, 2013

Mar. 31, 2014

Dec. 31, 2013

Mar. 31, 2014

Dec. 31, 2013

Mar. 31, 2014

Dec. 31, 2013

Mar. 31, 2014

Dec. 31, 2013

Mar. 31, 2014

Dec. 31, 2013

Mar. 31, 2014

Mar. 31, 2014

Mar. 31, 2014

Mar. 31, 2014

Mar. 31, 2014

Mar. 31, 2014

Uninsured Risk [Member]

Uninsured Risk [Member]

Uninsured Risk [Member]

Uninsured Risk [Member]

Uninsured Risk [Member]

Uninsured Risk [Member]

Performance Standby [Member]

Performance Standby [Member]

Performance Standby [Member]

Performance Standby [Member]

Financial Standby [Member]

Financial Standby [Member]

Surety Bond [Member]

Surety Bond [Member]

Subsidiary [Member]

Pending Litigation [Member]

Pending Litigation [Member]

Pending Litigation [Member]

Pending Litigation [Member]

Pending Litigation [Member]

Other Non-Current Assets [Member]

Other Non-Current Assets [Member]

Workers Compensation, General And Automobile Policies [Member]

Workers Compensation, General And Automobile Policies [Member]

Group Insurance Policies [Member]

Group Insurance Policies [Member]

Plan [Member]

Plan [Member]

Uninsured Risk [Member]

Uninsured Risk [Member]

Uninsured Risk [Member]

Uninsured Risk [Member]

Sunlight Entities [Member]

Sunlight Entities [Member]

Sunlight General Somerset [Member]

Sunlight General Morris [Member]

Sunlight General Sussex [Member]

Health Insurance [Member]

Health Insurance [Member]

Workers Compensation [Member]

Workers Compensation [Member]

Construction Contracts [Member]

Commitments and Contingencies [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Pending litigation, number

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

3

3

'

'

'

Contract price, pending litigation

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

$29

$36

$26

Liens sought, pending litigation

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

50

'

'

'

'

Letters of credit, outstanding amount

134.7

134.8

'

'

'

'

'

'

'

'

'

'

57.4

57.4

'

'

'

'

'

'

'

'

Outstanding bonds, amount

'

'

'

'

'

'

'

'

1,000

1,100

'

'

'

'

10.9

10.9

'

'

'

'

'

'

Estimated cost to complete bonded projects

'

'

'

'

'

'

'

'

'

'

281.6

297.1

'

'

'

'

'

'

'

'

'

'

Self insurance reserve

'

'

'

'

50.9

50.8

1.9

2.1

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Self insurance reserve, non-current

'

'

'

'

32

31.3

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Cash collateral held by insurance carriers

'

'

$1.40

$1.40

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Other guarantees, description

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'In the ordinary course of its business, from time to time, MasTec guarantees the obligations of its subsidiaries, including obligations under certain contracts with customers, certain lease obligations and in some states, obligations in connection with obtaining contractorsb licenses.

'

'

'

'

'

General warranty, description

'MasTec also generally warrants the work it performs for a one to two year period following substantial completion of a project.

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Commitments_and_Contingencies_1

Commitments and Contingencies (Collective Bargaining Agreements and Multi-Employer Plans) (Narrative) (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2014	Nov. 15, 2011
Loss Contingencies [Line Items]	'	'
Multi-employer plans, collective bargaining arrangement, description	'Certain of MasTecbs subsidiaries are party to various collective bargaining agreements with unions representing certain of their employees. The agreements require the subsidiaries party to the agreements to pay specified wages, provide certain benefits to their union employees and contribute certain amounts to multi-employer pension plans and employee benefit trusts. The collective bargaining agreements expire at various times and have typically been renegotiated and renewed on terms similar to the ones contained in the expiring agreements.	'
Multi-Employer Plans, Pension [Member] | Withdrawal from Multi-Employer Defined Benefit Plan [Member] | Central States Southeast And Southwest Areas Pension Fund [Member]	'	'
Loss Contingencies [Line Items]	'	'
Loss contingency, evaluation of estimated loss	'On November 15, 2011, the Company, along with other members of the Pipe Line Contractors Association (bPLCAb), voluntarily withdrew from the Central States Southeast and Southwest Areas Pension Fund (bCentral Statesb), a defined benefit multi-employer pension plan that is in critical status. In connection with this withdrawal, a $6.4 million withdrawal liability was established based on an estimate provided by the Central States administrator of such liability as of the date of withdrawal. The Company began paying installments towards this withdrawal liability in 2013, of which $5.1 million was outstanding as of March 31, 2014. The Company withdrew from Central States in order to mitigate its liability in connection with the plan; however, Central States has asserted that the PLCA members did not effectively withdraw in 2011 and are, therefore, responsible for a withdrawal liability that includes 2011 contribution amounts. By letter dated March 14, 2013, Central States demanded $11 million in withdrawal liability from the Company, which included 2011 contribution amounts. The Company is vigorously opposing this demand because it believes that it legally and effectively withdrew from Central States on November 15, 2011. If Central States were to prevail in its assertion that the Company withdrew after that date, then the initial amount of the Companybs withdrawal liability would increase to approximately $11 million. In addition, if Central States were to undergo a mass withdrawal, as defined by ERISA and the Pension Benefit Guaranty Corporation, within the three year period commencing with the beginning of the calendar year during which the Company withdrew from the plan, there could be additional liability.	'
Withdrawal liability	$5.10	$6.40
Maximum loss	$11	'

Commitments_and_Contingencies_2

Commitments and Contingencies (Concentrations of Risk) (Narrative) (Details)	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Concentration Risk [Line Items]	'	'
Number of customers	290	'
Ten Largest Customers [Member] | Customer Concentration Risk [Member] | Revenue [Member]	'	'
Concentration Risk [Line Items]	'	'
Significant customer, percentage of consolidated revenue	73.00%	69.00%

Related_Party_Transactions_Nar

Related Party Transactions (Narrative) (Details) (USD $)

3 Months Ended

3 Months Ended

3 Months Ended

3 Months Ended

Mar. 31, 2014

Nov. 08, 2013

Mar. 31, 2014

Mar. 31, 2014

Mar. 31, 2013

Dec. 31, 2013

Mar. 31, 2014

Mar. 31, 2013

Dec. 31, 2013

Mar. 31, 2014

Dec. 31, 2013

Mar. 31, 2014

Mar. 31, 2013

Mar. 31, 2014

Mar. 31, 2013

Management [Member]

Management [Member]

Management [Member]

Management [Member]

Management [Member]

Management [Member]

Management [Member]

Management [Member]

Management [Member]

Management [Member]

Management [Member]

Board of Directors Chairman [Member]

Board of Directors Chairman [Member]

Chief Executive Officer [Member]

Chief Executive Officer [Member]

Investment [Member]

Investment [Member]

Lease Agreements [Member]

Employee Leasing Arrangements [Member]

Employee Leasing Arrangements [Member]

Employee Leasing Arrangements [Member]

Service Agreements [Member]

Service Agreements [Member]

Service Agreements [Member]

Deferred Compensation, Excluding Share-based Payments and Retirement Benefits [Member]

Deferred Compensation, Excluding Share-based Payments and Retirement Benefits [Member]

Deferred Compensation, Excluding Share-based Payments and Retirement Benefits [Member]

Deferred Compensation, Excluding Share-based Payments and Retirement Benefits [Member]

Deferred Compensation, Excluding Share-based Payments and Retirement Benefits [Member]

Deferred Compensation, Excluding Share-based Payments and Retirement Benefits [Member]

Cross Country Pipeline [Member]

Cross Country Pipeline [Member]

Cross Country Pipeline [Member]

Related Customer [Member]

Related Customer [Member]

Related Customer [Member]

Related Customer [Member]

Related Customer [Member]

Related Customer [Member]

Other Long-Term Assets [Member]

Other Long-Term Assets [Member]

Machinery and Equipment [Member]

Related Party Transaction [Line Items]

'

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Cost method investment, original cost

'

$15,000,000

'

'

'

'

'

'

'

'

'

'

'

'

'

Cost method investments, additional information

'14.85% ownership interest

'

'

'

'

'

'

'

'

'

'

'

'

'

'

Expenses from transactions with related party

'

'

900,000

'

'

'

'

'

'

'

'

'

'

'

'

Charges to related party

'

'

'

200,000

100,000

'

'

'

'

'

'

'

'

'

'

Due from related party

'

'

'

100,000

'

100,000

'

'

'

'

'

'

'

'

'

Revenue from related party

'

'

'

'

'

'

300,000

300,000

'

'

'

'

'

'

'

Accounts receivable, related party

'

'

'

'

'

'

400,000

'

400,000

'

'

'

'

'

'

Payments for life insurance policies

'

'

'

'

'

'

'

'

'

'

'

0

0

0

0

Carrying amount, life insurance policies

'

'

'

'

'

'

'

'

'

$10,100,000

$10,200,000

'

'

'

'

Supplemental_Guarantor_Condens2

Supplemental Guarantor Condensed Unaudited Consolidating Financial Information (Narrative) (Details)	3 Months Ended
	Mar. 31, 2014
Unsecured Debt [Member] | Senior Notes [Member] | 4.875% Senior Notes [Member]	'
Condensed Unaudited Consolidating Financial Statements [Line Items]	'
Debt instrument, interest rate	4.88%
Guarantor Subsidiaries [Member]	'
Condensed Unaudited Consolidating Financial Statements [Line Items]	'
Percentage of voting interests owned, guarantor subsidiaries	100.00%

Supplemental_Guarantor_Condens3

Supplemental Guarantor Condensed Unaudited Consolidating Financial Information (Condensed Unaudited Consolidating Statements Of Operations and Comprehensive Income) (Details) (USD $)	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Condensed Unaudited Consolidating Statements of Operations and Comprehensive Income [Line Items]	'	'
Revenue	$964,029,000	$918,648,000
Costs of revenue, excluding depreciation and amortization	841,054,000	791,499,000
Depreciation and amortization	33,494,000	31,753,000
General and administrative expenses	53,327,000	48,885,000
Interest expense, net	12,003,000	10,045,000
Loss on extinguishment of debt	0	5,624,000
Other (income) expense, net	-1,955,000	-826,000
Income from continuing operations before income taxes	26,106,000	31,668,000
Benefit from (provision for) income taxes	-9,916,000	-12,348,000
Net income from continuing operations	16,190,000	19,320,000
Net loss from discontinued operations	-122,000	-947,000
Equity in income from subsidiaries, net of tax	0	0
Net income	16,068,000	18,373,000
Net income attributable to non-controlling interests	45,000	3,000
Net income attributable to MasTec, Inc.	16,023,000	18,370,000
Comprehensive income (loss)	10,733,000	17,770,000
Eliminations [Member]	'	'
Condensed Unaudited Consolidating Statements of Operations and Comprehensive Income [Line Items]	'	'
Revenue	0	-1,700,000
Costs of revenue, excluding depreciation and amortization	0	-1,700,000
Depreciation and amortization	0	0
General and administrative expenses	0	0
Interest expense, net	0	0
Loss on extinguishment of debt	'	0
Other (income) expense, net	0	0
Income from continuing operations before income taxes	0	0
Benefit from (provision for) income taxes	0	0
Net income from continuing operations	0	0
Net loss from discontinued operations	0	0
Equity in income from subsidiaries, net of tax	-16,400,000	-18,800,000
Net income	-16,400,000	-18,800,000
Net income attributable to non-controlling interests	0	0
Net income attributable to MasTec, Inc.	-16,400,000	-18,800,000
Comprehensive income (loss)	-11,000,000	-18,000,000
MasTec, Inc. [Member]	'	'
Condensed Unaudited Consolidating Statements of Operations and Comprehensive Income [Line Items]	'	'
Revenue	0	0
Costs of revenue, excluding depreciation and amortization	0	0
Depreciation and amortization	0	0
General and administrative expenses	600,000	300,000
Interest expense, net	0	0
Loss on extinguishment of debt	'	0
Other (income) expense, net	0	0
Income from continuing operations before income taxes	-600,000	-300,000
Benefit from (provision for) income taxes	200,000	100,000
Net income from continuing operations	-400,000	-200,000
Net loss from discontinued operations	0	0
Equity in income from subsidiaries, net of tax	16,400,000	18,800,000
Net income	16,000,000	18,600,000
Net income attributable to non-controlling interests	0	0
Net income attributable to MasTec, Inc.	16,000,000	18,600,000
Comprehensive income (loss)	10,600,000	17,800,000
Guarantor Subsidiaries [Member]	'	'
Condensed Unaudited Consolidating Statements of Operations and Comprehensive Income [Line Items]	'	'
Revenue	793,100,000	843,100,000
Costs of revenue, excluding depreciation and amortization	689,800,000	721,200,000
Depreciation and amortization	27,400,000	28,900,000
General and administrative expenses	47,300,000	45,100,000
Interest expense, net	11,700,000	10,000,000
Loss on extinguishment of debt	'	5,600,000
Other (income) expense, net	-2,100,000	-900,000
Income from continuing operations before income taxes	19,000,000	33,200,000
Benefit from (provision for) income taxes	-9,400,000	-13,000,000
Net income from continuing operations	9,600,000	20,200,000
Net loss from discontinued operations	0	0
Equity in income from subsidiaries, net of tax	0	0
Net income	9,600,000	20,200,000
Net income attributable to non-controlling interests	0	0
Net income attributable to MasTec, Inc.	9,600,000	20,200,000
Comprehensive income (loss)	9,500,000	20,500,000
Non-Guarantor Subsidiaries [Member]	'	'
Condensed Unaudited Consolidating Statements of Operations and Comprehensive Income [Line Items]	'	'
Revenue	170,900,000	77,200,000
Costs of revenue, excluding depreciation and amortization	151,300,000	72,000,000
Depreciation and amortization	6,100,000	2,900,000
General and administrative expenses	5,400,000	3,500,000
Interest expense, net	300,000	0
Loss on extinguishment of debt	'	0
Other (income) expense, net	100,000	0
Income from continuing operations before income taxes	7,700,000	-1,200,000
Benefit from (provision for) income taxes	-700,000	500,000
Net income from continuing operations	7,000,000	-700,000
Net loss from discontinued operations	-100,000	-900,000
Equity in income from subsidiaries, net of tax	0	0
Net income	6,900,000	-1,600,000
Net income attributable to non-controlling interests	100,000	0
Net income attributable to MasTec, Inc.	6,800,000	-1,600,000
Comprehensive income (loss)	$1,600,000	($2,500,000)

Supplemental_Guarantor_Condens4

Supplemental Guarantor Condensed Unaudited Consolidating Financial Information (Condensed Unaudited Consolidating Balance Sheets) (Details) (USD $)	Mar. 31, 2014	Dec. 31, 2013
Assets	'	'
Current assets, including discontinued operations	$1,357,936,000	$1,306,223,000
Property and equipment, net	509,585,000	488,132,000
Goodwill and other intangible assets, net	1,084,500,000	1,066,100,000
Net investments in and advances to (from) consolidated affilliates	0	0
Other long-term assets, including disontinued operations	61,439,000	60,552,000
Total assets	3,013,407,000	2,920,967,000
Liabilities and Equity	'	'
Total current liabilities	820,389,000	826,746,000
Long-term debt	841,335,000	765,425,000
Other liabilities	314,900,000	307,800,000
Total liabilities	1,976,560,000	1,899,910,000
Total equity	1,036,847,000	1,021,057,000
Total liabilities and equity	3,013,407,000	2,920,967,000
Eliminations [Member]	'	'
Assets	'	'
Current assets, including discontinued operations	0	0
Property and equipment, net	0	0
Goodwill and other intangible assets, net	0	0
Net investments in and advances to (from) consolidated affilliates	-1,171,400,000	-1,155,100,000
Other long-term assets, including disontinued operations	0	0
Total assets	-1,171,400,000	-1,155,100,000
Liabilities and Equity	'	'
Total current liabilities	0	0
Long-term debt	0	0
Other liabilities	0	0
Total liabilities	0	0
Total equity	-1,171,400,000	-1,155,100,000
Total liabilities and equity	-1,171,400,000	-1,155,100,000
MasTec, Inc. [Member]	'	'
Assets	'	'
Current assets, including discontinued operations	0	0
Property and equipment, net	0	0
Goodwill and other intangible assets, net	0	0
Net investments in and advances to (from) consolidated affilliates	1,022,500,000	1,006,800,000
Other long-term assets, including disontinued operations	9,300,000	9,300,000
Total assets	1,031,800,000	1,016,100,000
Liabilities and Equity	'	'
Total current liabilities	0	0
Long-term debt	0	0
Other liabilities	0	0
Total liabilities	0	0
Total equity	1,031,800,000	1,016,100,000
Total liabilities and equity	1,031,800,000	1,016,100,000
Guarantor Subsidiaries [Member]	'	'
Assets	'	'
Current assets, including discontinued operations	1,165,300,000	1,155,900,000
Property and equipment, net	435,900,000	420,200,000
Goodwill and other intangible assets, net	931,800,000	933,900,000
Net investments in and advances to (from) consolidated affilliates	173,900,000	172,400,000
Other long-term assets, including disontinued operations	36,900,000	36,200,000
Total assets	2,743,800,000	2,718,600,000
Liabilities and Equity	'	'
Total current liabilities	735,700,000	773,300,000
Long-term debt	833,300,000	760,900,000
Other liabilities	236,700,000	236,700,000
Total liabilities	1,805,700,000	1,770,900,000
Total equity	938,100,000	947,700,000
Total liabilities and equity	2,743,800,000	2,718,600,000
Non-Guarantor Subsidiaries [Member]	'	'
Assets	'	'
Current assets, including discontinued operations	192,600,000	150,300,000
Property and equipment, net	73,700,000	67,900,000
Goodwill and other intangible assets, net	152,700,000	132,200,000
Net investments in and advances to (from) consolidated affilliates	-25,000,000	-24,100,000
Other long-term assets, including disontinued operations	15,200,000	15,100,000
Total assets	409,200,000	341,400,000
Liabilities and Equity	'	'
Total current liabilities	84,700,000	53,400,000
Long-term debt	8,000,000	4,500,000
Other liabilities	78,200,000	71,100,000
Total liabilities	170,900,000	129,000,000
Total equity	238,300,000	212,400,000
Total liabilities and equity	$409,200,000	$341,400,000

Supplemental_Guarantor_Condens5

Supplemental Guarantor Condensed Unaudited Consolidating Financial Information (Condensed Unaudited Consolidating Statements Of Cash Flows) (Details) (USD $)	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Condensed Unaudited Consolidating Statements of Cash Flows [Line Items]	'	'
Net cash (used in) provided by operating activities	($20,394,000)	$26,130,000
Cash flows (used in) provided by investing activities:	'	'
Cash paid for acquisitions, net of cash acquired	-23,831,000	-4,653,000
Capital expenditures	-35,554,000	-25,851,000
Proceeds from sale of property and equipment	3,373,000	3,411,000
Payments for other investments	-1,098,000	0
Net cash used in investing activities	-57,110,000	-27,093,000
Cash flows provided by (used in) financing activities:	'	'
Proceeds from (repayments of) credit facility	76,500,000	-134,000,000
Proceeds from senior notes, net	'	250,000,000
Repayments of other borrowings and capital lease obligations	-13,800,000	-19,100,000
Payments of financing costs, including call premiums on extinguishment of debt	-218,000	-10,968,000
Net financing activities and advances (to) from consolidated affiliates	0	0
Net cash provided by financing activities	64,314,000	84,365,000
Net (decrease) increase in cash and cash equivalents	-13,190,000	83,402,000
Net effect of currency translation on cash	-476,000	-60,000
Cash and cash equivalents - beginning of period	22,927,000	26,767,000
Cash and cash equivalents - end of period	9,261,000	110,109,000
Cash and cash equivalents of discontinued operations	0	862,000
Cash and cash equivalents of continuing operations	9,261,000	109,247,000
Earn-out Arrangements [Member]	'	'
Cash flows provided by (used in) financing activities:	'	'
Proceeds from (payments for) other financing activities	0	-5,003,000
Stock Compensation Plan [Member]	'	'
Cash flows provided by (used in) financing activities:	'	'
Proceeds from (payments for) other financing activities	1,800,000	3,500,000
Eliminations [Member]	'	'
Condensed Unaudited Consolidating Statements of Cash Flows [Line Items]	'	'
Net cash (used in) provided by operating activities	0	0
Cash flows (used in) provided by investing activities:	'	'
Cash paid for acquisitions, net of cash acquired	0	0
Capital expenditures	0	0
Proceeds from sale of property and equipment	0	0
Payments for other investments	0	'
Net cash used in investing activities	0	0
Cash flows provided by (used in) financing activities:	'	'
Proceeds from (repayments of) credit facility	0	0
Proceeds from senior notes, net	'	0
Repayments of other borrowings and capital lease obligations	0	0
Payments of financing costs, including call premiums on extinguishment of debt	0	0
Net financing activities and advances (to) from consolidated affiliates	0	0
Net cash provided by financing activities	0	0
Net (decrease) increase 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
Eliminations [Member] | Earn-out Arrangements [Member]	'	'
Cash flows provided by (used in) financing activities:	'	'
Proceeds from (payments for) other financing activities	'	0
Eliminations [Member] | Stock Compensation Plan [Member]	'	'
Cash flows provided by (used in) financing activities:	'	'
Proceeds from (payments for) other financing activities	0	0
MasTec, Inc. [Member]	'	'
Condensed Unaudited Consolidating Statements of Cash Flows [Line Items]	'	'
Net cash (used in) provided by operating activities	-300,000	-600,000
Cash flows (used in) provided by investing activities:	'	'
Cash paid for acquisitions, net of cash acquired	0	0
Capital expenditures	0	0
Proceeds from sale of property and equipment	0	0
Payments for other investments	0	'
Net cash used in investing activities	0	0
Cash flows provided by (used in) financing activities:	'	'
Proceeds from (repayments of) credit facility	0	0
Proceeds from senior notes, net	'	0
Repayments of other borrowings and capital lease obligations	0	0
Payments of financing costs, including call premiums on extinguishment of debt	0	0
Net financing activities and advances (to) from consolidated affiliates	-800,000	-2,200,000
Net cash provided by financing activities	300,000	600,000
Net (decrease) increase 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
MasTec, Inc. [Member] | Earn-out Arrangements [Member]	'	'
Cash flows provided by (used in) financing activities:	'	'
Proceeds from (payments for) other financing activities	'	0
MasTec, Inc. [Member] | Stock Compensation Plan [Member]	'	'
Cash flows provided by (used in) financing activities:	'	'
Proceeds from (payments for) other financing activities	1,100,000	2,800,000
Guarantor Subsidiaries [Member]	'	'
Condensed Unaudited Consolidating Statements of Cash Flows [Line Items]	'	'
Net cash (used in) provided by operating activities	15,200,000	50,300,000
Cash flows (used in) provided by investing activities:	'	'
Cash paid for acquisitions, net of cash acquired	-23,800,000	-4,700,000
Capital expenditures	-32,600,000	-25,400,000
Proceeds from sale of property and equipment	3,400,000	3,400,000
Payments for other investments	-1,100,000	'
Net cash used in investing activities	-54,100,000	-26,700,000
Cash flows provided by (used in) financing activities:	'	'
Proceeds from (repayments of) credit facility	76,500,000	-134,000,000
Proceeds from senior notes, net	'	250,000,000
Repayments of other borrowings and capital lease obligations	-12,900,000	-19,100,000
Payments of financing costs, including call premiums on extinguishment of debt	-200,000	-11,000,000
Net financing activities and advances (to) from consolidated affiliates	-24,700,000	-12,900,000
Net cash provided by financing activities	39,400,000	68,700,000
Net (decrease) increase in cash and cash equivalents	500,000	92,300,000
Net effect of currency translation on cash	0	-100,000
Cash and cash equivalents - beginning of period	5,300,000	12,700,000
Cash and cash equivalents - end of period	5,800,000	104,900,000
Cash and cash equivalents of discontinued operations	0	0
Cash and cash equivalents of continuing operations	5,800,000	104,900,000
Guarantor Subsidiaries [Member] | Earn-out Arrangements [Member]	'	'
Cash flows provided by (used in) financing activities:	'	'
Proceeds from (payments for) other financing activities	'	-5,000,000
Guarantor Subsidiaries [Member] | Stock Compensation Plan [Member]	'	'
Cash flows provided by (used in) financing activities:	'	'
Proceeds from (payments for) other financing activities	700,000	700,000
Non-Guarantor Subsidiaries [Member]	'	'
Condensed Unaudited Consolidating Statements of Cash Flows [Line Items]	'	'
Net cash (used in) provided by operating activities	-35,300,000	-23,600,000
Cash flows (used in) provided by investing activities:	'	'
Cash paid for acquisitions, net of cash acquired	0	0
Capital expenditures	-3,000,000	-400,000
Proceeds from sale of property and equipment	0	0
Payments for other investments	0	'
Net cash used in investing activities	-3,000,000	-400,000
Cash flows provided by (used in) financing activities:	'	'
Proceeds from (repayments of) credit facility	0	0
Proceeds from senior notes, net	'	0
Repayments of other borrowings and capital lease obligations	-900,000	0
Payments of financing costs, including call premiums on extinguishment of debt	0	0
Net financing activities and advances (to) from consolidated affiliates	25,500,000	15,100,000
Net cash provided by financing activities	24,600,000	15,100,000
Net (decrease) increase in cash and cash equivalents	-13,700,000	-8,900,000
Net effect of currency translation on cash	-500,000	0
Cash and cash equivalents - beginning of period	17,700,000	14,100,000
Cash and cash equivalents - end of period	3,500,000	5,200,000
Cash and cash equivalents of discontinued operations	0	900,000
Cash and cash equivalents of continuing operations	3,500,000	4,300,000
Non-Guarantor Subsidiaries [Member] | Earn-out Arrangements [Member]	'	'
Cash flows provided by (used in) financing activities:	'	'
Proceeds from (payments for) other financing activities	'	0
Non-Guarantor Subsidiaries [Member] | Stock Compensation Plan [Member]	'	'
Cash flows provided by (used in) financing activities:	'	'
Proceeds from (payments for) other financing activities	$0	$0