Commitments and Contingencies	9 Months Ended
Sep. 30, 2013
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. Legacy Litigation MasTec is subject to litigation, some of which dates from the period 2001 through 2006. Sintel. The labor union representing the workers of Sistemas e Instalaciones de Telecomunicacion S.A. (“Sintel”), a former MasTec subsidiary that was sold in 1998, filed a claim that initiated an investigative action with the Audiencia Nacional, a Spanish federal court, against Telefonica and dozens of other defendants including current and former officers and directors of MasTec and Sintel, relating to Sintel’s 2000 bankruptcy. On June 17, 2013, MasTec, the workers and the prosecutor resolved the matter, resulting in the dismissal all of the charges and claims brought against MasTec and the MasTec defendants. The workers provided MasTec and MasTec defendants with a release and an acknowledgment that MasTec and MasTec defendants acted in good faith and did not cause Sintel's bankruptcy. On June 20, 2013, the Audiencia Nacional issued an order dismissing the charges and claims against MasTec and the MasTec defendants and finding another party guilty and liable of certain charges. The Company resolved the matter in order to avoid significant legal fees and the potential liabilities resulting from the actions of other Spanish defendants for which MasTec may be financially responsible under a theory of subsidiary (or vicarious) liability, the uncertainty of a trial before a foreign tribunal such as the Audiencia Nacional and to eliminate management time devoted to this matter. MasTec recorded a pre-tax charge of $9.6 million in 2012 in connection with this matter and recorded an additional pre-tax charge of $2.8 million during the second quarter of 2013 in connection with its resolution. Other Outstanding Litigation SunLight Entities. In 2011, Power Partners MasTec, LLC., a MasTec, Inc. subsidiary (“Power Partners”), entered into engineering, procurement, and construction agreements (“Contracts”) 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 county improvement authorities. Power Partners and the SunLight Entities have 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. Discovery is ongoing. The arbitrations are scheduled to begin in January 2014. Power Partners has also filed municipal liens and construction liens for the work performed. The liens have been challenged, and the Company is currently appealing the trial court's adverse ruling to the New Jersey appellate court. Power Partners is vigorously pursuing its claims against the SunLight Entities and vigorously defending against claims by the SunLight Entities. City of Marathon. During 2010 and 2011, pursuant to a written contract, the Company provided certain construction services for the City of Marathon in Marathon, Florida. The Company completed those services in 2011, but at the end of 2011, the Company had still not been paid for all of the work performed on the project. The Company is seeking in excess of $6 million against the City of Marathon for breach of contract and against the City of Marathon’s engineers for professional negligence. The City of Marathon and the engineers filed answers denying liability and claiming that the Company breached the contract. Discovery is ongoing. The Company will continue to vigorously pursue these claims. 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 11 - 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. As of September 30, 2013 and December 31, 2012, the Company had $138.5 million and $120.8 million, respectively, of letters of credit issued under its Credit Facility, of which $52.2 million and $53.2 million, respectively, pertained to certain of the Company's insurance carriers. The Company is not aware of any material claims relating to outstanding letters of credit as of September 30, 2013 or December 31, 2012. 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. As of September 30, 2013, the estimated cost to complete of the projects secured by the Company’s $1.4 billion in performance and payment bonds was $383.8 million. As of December 31, 2012, the estimated cost to complete of the projects secured by the Company’s $1.1 billion in performance and payment bonds was $284.5 million. Self-Insurance. MasTec maintains insurance policies subject to per claim deductibles of $1 million for its workers’ compensation policy, $2 million for its general liability policy and $2 million for its automobile liability policy. The Company has excess umbrella coverage up to $100 million per claim and in the aggregate. As of September 30, 2013 and December 31, 2012, 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 $53.1 million and $48.1 million, respectively, of which $32.6 million and $28.5 million, respectively, was reflected within non-current other liabilities in the condensed unaudited consolidated financial statements. MasTec also maintains an insurance policy with respect to employee group health claims, which is subject to annual per employee maximum losses of $0.4 million. MasTec’s liability for employee group claims as of September 30, 2013 and December 31, 2012 was $1.0 million and $1.1 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 in which the Company is self-insured. As of September 30, 2013 and December 31, 2012, these letters of credit amounted to $52.2 million and $53.2 million, respectively. In addition, cash collateral deposited with insurance carriers, which is included in other long-term assets in the consolidated balance sheets, amounted to $1.5 million and $2.0 million as of September 30, 2013 and December 31, 2012, respectively. Outstanding surety bonds related to workers’ compensation self-insurance programs amounted to $10.9 million and $9.0 million as of September 30, 2013 and December 31, 2012, respectively. 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 Pension 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 multi-employer pension plan contribution rates are determined annually and assessed on a “pay-as-you-go” basis based on union employee payrolls. 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 required amount of future contributions cannot be determined for future periods because the number of union employees employed at any given time, and the plans in which they participate, vary depending upon the location and number of ongoing projects and the need for union resources in connection with those projects. Based upon the information available to the Company from plan administrators as of September 30, 2013, 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 $5.7 million was outstanding as of September 30, 2013. 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 made a demand on the Company for the sum of $10.8 million in withdrawal liability, which sum 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, in fact, withdrew after that date, then the amount of the Company’s withdrawal liability would increase to approximately $10.8 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. See Note 13 - Other Retirement Plans for details of the Company's participation in multi-employer pension plans. 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 September 30, 2013 and December 31, 2012, 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.

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.

Legacy Litigation

MasTec is subject to litigation, some of which dates from the period 2001 through 2006.

Sintel. The labor union representing the workers of Sistemas e Instalaciones de Telecomunicacion S.A. (“Sintel”), a former MasTec subsidiary that was sold in 1998, filed a claim that initiated an investigative action with the Audiencia Nacional, a Spanish federal court, against Telefonica and dozens of other defendants including current and former officers and directors of MasTec and Sintel, relating to Sintel’s 2000 bankruptcy.

On June 17, 2013, MasTec, the workers and the prosecutor resolved the matter, resulting in the dismissal all of the charges and claims brought against MasTec and the MasTec defendants. The workers provided MasTec and MasTec defendants with a release and an acknowledgment that MasTec and MasTec defendants acted in good faith and did not cause Sintel's bankruptcy. On June 20, 2013, the Audiencia Nacional issued an order dismissing the charges and claims against MasTec and the MasTec defendants and finding another party guilty and liable of certain charges.

The Company resolved the matter in order to avoid significant legal fees and the potential liabilities resulting from the actions of other Spanish defendants for which MasTec may be financially responsible under a theory of subsidiary (or vicarious) liability, the uncertainty of a trial before a foreign tribunal such as the Audiencia Nacional and to eliminate management time devoted to this matter. MasTec recorded a pre-tax charge of $9.6 million in 2012 in connection with this matter and recorded an additional pre-tax charge of $2.8 million during the second quarter of 2013 in connection with its resolution.

Other Outstanding Litigation

SunLight Entities. In 2011, Power Partners MasTec, LLC., a MasTec, Inc. subsidiary (“Power Partners”), entered into engineering, procurement, and construction agreements (“Contracts”) 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 county improvement authorities.

Power Partners and the SunLight Entities have 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. Discovery is ongoing. The arbitrations are scheduled to begin in January 2014.

Power Partners has also filed municipal liens and construction liens for the work performed. The liens have been challenged, and the Company is currently appealing the trial court's adverse ruling to the New Jersey appellate court. Power Partners is vigorously pursuing its claims against the SunLight Entities and vigorously defending against claims by the SunLight Entities.

City of Marathon. During 2010 and 2011, pursuant to a written contract, the Company provided certain construction services for the City of Marathon in Marathon, Florida. The Company completed those services in 2011, but at the end of 2011, the Company had still not been paid for all of the work performed on the project. The Company is seeking in excess of $6 million against the City of Marathon for breach of contract and against the City of Marathon’s engineers for professional negligence. The City of Marathon and the engineers filed answers denying liability and claiming that the Company breached the contract. Discovery is ongoing. The Company will continue to vigorously pursue these claims.

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 11 - 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. As of September 30, 2013 and December 31, 2012, the Company had $138.5 million and $120.8 million, respectively, of letters of credit issued under its Credit Facility, of which $52.2 million and $53.2 million, respectively, pertained to certain of the Company's insurance carriers. The Company is not aware of any material claims relating to outstanding letters of credit as of September 30, 2013 or December 31, 2012.

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. As of September 30, 2013, the estimated cost to complete of the projects secured by the Company’s $1.4 billion in performance and payment bonds was $383.8 million. As of December 31, 2012, the estimated cost to complete of the projects secured by the Company’s $1.1 billion in performance and payment bonds was $284.5 million.

Self-Insurance. MasTec maintains insurance policies subject to per claim deductibles of $1 million for its workers’ compensation policy, $2 million for its general liability policy and $2 million for its automobile liability policy. The Company has excess umbrella coverage up to $100 million per claim and in the aggregate. As of September 30, 2013 and December 31, 2012, 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 $53.1 million and $48.1 million, respectively, of which $32.6 million and $28.5 million, respectively, was reflected within non-current other liabilities in the condensed unaudited consolidated financial statements. MasTec also maintains an insurance policy with respect to employee group health claims, which is subject to annual per employee maximum losses of $0.4 million. MasTec’s liability for employee group claims as of September 30, 2013 and December 31, 2012 was $1.0 million and $1.1 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 in which the Company is self-insured. As of September 30, 2013 and December 31, 2012, these letters of credit amounted to $52.2 million and $53.2 million, respectively. In addition, cash collateral deposited with insurance carriers, which is included in other long-term assets in the consolidated balance sheets, amounted to $1.5 million and $2.0 million as of September 30, 2013 and December 31, 2012, respectively. Outstanding surety bonds related to workers’ compensation self-insurance programs amounted to $10.9 million and $9.0 million as of September 30, 2013 and December 31, 2012, respectively.

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 Pension 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 multi-employer pension plan contribution rates are determined annually and assessed on a “pay-as-you-go” basis based on union employee payrolls. 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 required amount of future contributions cannot be determined for future periods because the number of union employees employed at any given time, and the plans in which they participate, vary depending upon the location and number of ongoing projects and the need for union resources in connection with those projects. Based upon the information available to the Company from plan administrators as of September 30, 2013, 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 $5.7 million was outstanding as of September 30, 2013. 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 made a demand on the Company for the sum of $10.8 million in withdrawal liability, which sum 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, in fact, withdrew after that date, then the amount of the Company’s withdrawal liability would increase to approximately $10.8 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.

See Note 13 - Other Retirement Plans for details of the Company's participation in multi-employer pension plans.

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 September 30, 2013 and December 31, 2012, 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.