Commitments and Contingencies	3 Months Ended
Mar. 31, 2019
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	COMMITMENTS AND CONTINGENCIES: Investments in Affiliates and Other Entities As described in Note 9, Quanta holds investments in various entities, including joint venture entities that provide infrastructure services under specific customer contracts and partially owned entities that own and operate certain infrastructure assets constructed by Quanta. Losses incurred by these entities are generally shared ratably based on the percentage ownership of the participants in these structures. However, in Quanta’s joint venture structures that provide infrastructure services, each participant is typically jointly and severally liable for all of the obligations of the joint venture entity pursuant to the contract with the customer, as a general partner or through a parent guarantee and, therefore, can be liable for full performance of the contract with the customer. In circumstances where Quanta’s participation in a joint venture qualifies as a general partnership, the joint venture partners are jointly and severally liable for all of the obligations of the joint venture, including obligations owed to the customer or any other person or entity. Quanta is not aware of circumstances that would lead to future claims against it for material amounts in connection with these joint and several liabilities. Additionally, in the joint venture structures entered into by Quanta, typically each party indemnifies the other party for any liabilities incurred in excess of the liabilities such other party is obligated to bear under the respective joint venture agreement or in accordance with the scope of work subcontracted to each party. It is possible, however, that Quanta could be required to pay or perform obligations in excess of its share if the other party is unable or refuses to pay or perform its share of the obligations. Quanta is not aware of circumstances that would lead to future claims against it for material amounts that would not be indemnified. As described in Note 2, Quanta has also formed a partnership with select infrastructure investors that provides up to $1.0 billion of capital, including approximately $80.0 million from Quanta, available to invest in certain specified infrastructure projects through August 2024. As of March 31, 2019, Quanta had contributed $15.1 million to this partnership in connection with certain investments and the payment of management fees. Additionally, as of March 31, 2019, Quanta had outstanding capital commitments associated with investments in unconsolidated affiliates related to planned oil and gas infrastructure projects of $2.3 million, of which $1.6 million is expected to be paid in 2019. The remaining $0.7 million of these capital commitments is anticipated to be paid by May 31, 2022. During 2014, a limited partnership in which Quanta is a partner was selected for an engineering, procurement and construction (EPC) electric transmission project in Canada to construct approximately 500 kilometers of transmission line and two 500 kV substations. A subsidiary of Quanta, engaged by the limited partnership, is contracted to provide turnkey EPC services for the entire project. As of March 31, 2019, Quanta made aggregate contributions to this unconsolidated affiliate of $88.7 million, received $60.6 million as a return of capital and had no outstanding additional capital commitments associated with this project. Contingent Consideration Liabilities As discussed in further detail in Note 2, Quanta is obligated to pay contingent consideration amounts to the former owners of certain acquired businesses in the event that such acquired businesses achieve specified performance objectives. As of March 31, 2019 and December 31, 2018, the estimated fair value of Quanta’s contingent consideration liabilities totaled $70.7 million and $70.8 million. Committed Expenditures Quanta has capital commitments for the expansion of its vehicle fleet in order to accommodate manufacturer lead times on certain types of vehicles. As of March 31, 2019, Quanta had $44.0 million of production orders with expected delivery dates in 2019. Although Quanta has committed to purchase these vehicles at the time of their delivery, Quanta anticipates that the majority of these orders will be assigned to third party leasing companies and made available under certain master equipment lease agreements, thereby releasing Quanta from its capital commitments. Legal Proceedings Quanta is from time to time party to various lawsuits, claims and other legal proceedings that arise in the ordinary course of business. These actions typically seek, among other things, compensation for alleged personal injury, breach of contract and/or property damages, employment-related damages, punitive damages, civil penalties or other losses, or injunctive or declaratory relief. With respect to all such lawsuits, claims and proceedings, Quanta records a reserve when it is probable that a liability has been incurred and the amount of loss can be reasonably estimated. In addition, Quanta discloses matters for which management believes a material loss is at least reasonably possible. Except as otherwise stated below, none of these proceedings are expected to have a material adverse effect on Quanta’s consolidated financial position, results of operations or cash flows. In all instances, management has assessed the matter based on current information and made a judgment concerning its potential outcome, giving due consideration to the nature of the claim, the amount and nature of damages sought and the probability of success. Management’s judgment may prove materially inaccurate, and such judgment is made subject to the known uncertainties of litigation. Maurepas Project Dispute. During the third quarter of 2017, Maurepas Pipeline, LLC (Maurepas) notified QPS Engineering, LLC (QPS), a subsidiary of Quanta, of Maurepas’ assertion of a claim for liquidated damages allegedly arising from delay in mechanical completion of a project in Louisiana. Quanta disputes the claim and believes that QPS is not responsible for liquidated damages under the contract terms. The matter remains subject to contractual dispute resolution measures; however, either party may choose to institute a formal legal proceeding upon completion of such measures. If, upon final resolution of this matter, Quanta is unsuccessful, any such liquidated damages would be recorded as additional costs on the project. As of March 31, 2019, Quanta had recorded an accrual with respect to this matter based on the current estimated amount of probable loss and believes that the range of any additional reasonably possible loss would be the difference between the accrued amount and $22.0 million, which is the maximum liability for liquidated damages pursuant to the contract terms. In July and August 2018, Quanta also received notice from Maurepas claiming certain warranty defects on the project. Quanta is evaluating the claimed defects, and based on information currently available, no estimate of reasonably possible loss related to the warranty claim can be determined. Lorenzo Benton v. Telecom Network Specialists, Inc., et al. In June 2006, plaintiff Lorenzo Benton filed a class action complaint in the Superior Court of California, County of Los Angeles, alleging various wage and hour violations against Telecom Network Specialists (TNS), a former subsidiary of Quanta. Quanta retained liability associated with this matter pursuant to the terms of Quanta’s sale of TNS in December 2012. Benton represents a class of workers that includes all persons who worked on certain TNS projects, including individuals that TNS retained through numerous staffing agencies. The plaintiff class in this matter is seeking damages for unpaid wages, penalties associated with the failure to provide meal and rest periods and overtime wages, interest and attorneys’ fees. In January 2017, the trial court granted a summary judgment motion filed by the plaintiff class and found that TNS was a joint employer of the class members and that it failed to provide adequate meal and rest breaks and failed to pay overtime wages. In February 2019, the court granted, in part, the plaintiff class’s final motion for summary judgment on damages awarding the class approximately $7.5 million for its meal/rest break and overtime claims, and denied the motion as to penalties. Quanta believes the court’s decisions on liability and damages are not supported by controlling law and continues to contest its liability and the damage calculation asserted by the plaintiff class in this matter. Additionally, in November 2007, TNS filed cross complaints for indemnity and breach of contract against the staffing agencies, which employed many of the individuals in question. In December 2012, the trial court heard cross-motions for summary judgment filed by TNS and the staffing agencies pertaining to TNS’s demand for indemnity. The court denied TNS’s motion and granted the motions filed by the staffing agencies; however, the California Appellate Court reversed the trial court’s decision in part and instructed the trial court to reconsider its ruling. In February 2017, the court denied a new motion for summary judgment filed by the staffing companies and has since stated that the staffing companies would be liable to TNS for any damages owed to the class members that the staffing companies employed. The final amount of liability, if any, payable in connection with this matter remains the subject of pending litigation and will ultimately depend on various factors, including the outcome of Quanta’s appeal of the trial court’s rulings on liability and damages, the final determination with respect to any additional damages owed by Quanta, and the solvency of the staffing agencies. Based on review and analysis of the trial court’s rulings on liability, Quanta does not believe, at this time, that it is probable this matter will result in a material loss. However, if Quanta is unsuccessful in this litigation and the staffing agencies are unable to fund damages owed to class members, Quanta believes the range of reasonably possible loss to Quanta upon final resolution of this matter could be up to approximately $11.0 million, plus attorneys’ fees and expenses of the plaintiff class. Concentrations of Credit Risk Quanta is subject to concentrations of credit risk related primarily to its cash and cash equivalents and its net receivable position with customers, which includes amounts related to billed and unbilled accounts receivable and contract assets net of advanced billings with the same customer. Substantially all of Quanta’s cash and cash equivalents are managed by what it believes to be high credit quality financial institutions. In accordance with Quanta’s investment policies, these institutions are authorized to invest cash and cash equivalents in a diversified portfolio of what Quanta believes to be high quality cash and cash equivalent investments, which consist primarily of interest-bearing demand deposits, money market investments and money market mutual funds. Although Quanta does not currently believe the principal amount of these cash and cash equivalents is subject to any material risk of loss, changes in economic conditions could impact the interest income Quanta receives from these investments. In addition, Quanta grants credit under normal payment terms, generally without collateral, to its customers, which include electric power and energy companies, governmental entities, general contractors, and builders, owners and managers of commercial and industrial properties located primarily in the United States, Canada, Australia and Latin America. Consequently, Quanta is subject to potential credit risk related to changes in business and economic factors throughout these locations, which may be heightened as a result of uncertain economic and financial market conditions that have existed in recent years. However, Quanta generally has certain statutory lien rights with respect to services provided. Some of Quanta’s customers have experienced significant financial difficulties (including bankruptcy), and customers may experience financial difficulties in the future. These difficulties expose Quanta to increased risk related to collectability of billed and unbilled receivables and contract assets for services Quanta has performed. On January 29, 2019, one of Quanta’s largest customers, PG&E, filed for bankruptcy protection under Chapter 11 of the U.S. Bankruptcy Code, as amended. Quanta is monitoring the bankruptcy proceeding and evaluating the treatment of, and potential claims related to, its pre-petition receivables. As of the bankruptcy filing date, Quanta had approximately $157 million of billed and unbilled receivables, which remained unpaid as of March 31, 2019. Subsequent to March 31, 2019, the bankruptcy court approved the assumption by PG&E of two substantial contracts with a subsidiary of Quanta, which authorizes PG&E to pay approximately $116 million of pre-petition receivables due under those contracts. As a result of the contract assumptions, Quanta expects to receive payment of the $116 million in the near term. Quanta also believes it will ultimately collect the remaining approximately $41 million of pre-petition receivables, and that amount has been classified as non-current within “Other assets, net” in the accompanying condensed consolidated balance sheet as of March 31, 2019. However, the ultimate outcome of the bankruptcy proceeding is uncertain, and Quanta’s belief regarding collection of the remaining receivables is based on a number of assumptions that are potentially subject to change as the proceeding progresses. Should any of those assumptions change, the amount collected could be materially less than the amount of the remaining receivables. Additionally, Quanta is continuing to perform services for PG&E while the bankruptcy case is ongoing and believes that amounts billed for post-petition services will continue to be collected in the ordinary course of business. At March 31, 2019 and December 31, 2018, no customer represented 10% or more of Quanta’s consolidated net receivable position. No customer represented 10% or more of Quanta’s consolidated revenues for the three months ended March 31, 2019 and March 31, 2018. Insurance As discussed in Note 2, Quanta is insured for employer’s liability, workers’ compensation, auto liability, general liability and group health claims. As of March 31, 2019 and December 31, 2018, the gross amount accrued for insurance claims totaled $268.7 million and $272.9 million, with $200.8 million and $210.1 million considered to be long-term and included in “Insurance and other non-current liabilities.” Related insurance recoveries/receivables as of March 31, 2019 and December 31, 2018 were $35.8 million and $56.5 million, of which $0.4 million and $0.3 million were included in “Prepaid expenses and other current assets” and $35.4 million and $56.2 million were included in “Other assets, net.” Project Insurance Claim. In June 2018, while performing a horizontal directional drill and installing an underground gas pipeline, one of Quanta’s subsidiaries experienced a partial collapse of a borehole. Subsequent to the incident, Quanta has been working with its customer to mitigate the impact of the incident and to complete the project; however, Quanta has encountered additional challenges due to the collapsed borehole. As required by the contract, the customer procured certain insurance coverage for the project, with the Quanta subsidiary as an additional insured. Quanta believes the incident is covered under such insurance and is working collaboratively with the customer to pursue insurance claims with the customer’s insurance carriers. To the extent such claims are not successful, Quanta would expect to pursue contractual relief from the customer. As of March 31, 2019, Quanta had recorded an insurance receivable of $45.8 million in accordance with GAAP related to accounting for insurance claims and potential recoveries. The amount represents a portion of the insurance claims being pursued as of such date. Quanta expects the insurance claims and the amount of the insurance receivable to increase in future periods as mitigation activities continue. The mitigation plan remains subject to inherent risks associated with underground pipeline installation, which could cause the costs to mitigate the incident to increase materially. The project is ongoing and the final amount of the insurance claims is not currently known. However, Quanta’s claims associated with the project, including both insurance claims and potential contractual claims, will be substantially in excess of the currently recognized receivable. To the extent Quanta is unsuccessful in realizing insurance or contractual recoveries, additional charges to operating results, which could be material, would be required. Letters of Credit Certain of Quanta’s vendors require letters of credit to ensure reimbursement for amounts they are disbursing on Quanta’s behalf, such as to beneficiaries under its insurance programs. In addition, from time to time, certain customers require Quanta to post letters of credit to ensure payment of subcontractors and vendors and guarantee performance under contracts. Such letters of credit are generally issued by a bank or similar financial institution, typically pursuant to Quanta’s senior secured credit facility. Each letter of credit commits the issuer to pay specified amounts to the holder of the letter of credit if the holder claims that Quanta has failed to perform specified actions. If this were to occur, Quanta would be required to reimburse the issuer of the letter of credit. Depending on the circumstances of such a reimbursement, Quanta may also be required to record a charge to earnings for the reimbursement. Quanta does not believe it is likely that any material claims will be made under a letter of credit in the foreseeable future. As of March 31, 2019, Quanta had $385.0 million in outstanding letters of credit and bank guarantees under its senior secured credit facility securing its casualty insurance program and various contractual commitments. These are irrevocable stand-by letters of credit with maturities generally expiring at various times throughout 2019 and 2020. Quanta expects to renew the majority of the letters of credit related to the casualty insurance program for subsequent one-year periods upon maturity. Performance Bonds and Parent Guarantees Many customers, particularly in connection with new construction, require Quanta to post performance and payment bonds issued by a financial institution known as a surety. These bonds provide a guarantee to the customer that Quanta will perform under the terms of a contract and pay its subcontractors and vendors. If Quanta fails to perform, the customer may demand that the surety make payments or provide services under the bond. Quanta must reimburse the surety for any expenses or outlays it incurs. Under Quanta’s underwriting, continuing indemnity and security agreement with its sureties and with the consent of the lenders that are party to Quanta’s credit agreement, Quanta has granted security interests in certain of our assets as collateral for its obligations to the sureties. Subject to certain conditions and consistent with terms of Quanta’s credit agreement, these security interests will be automatically released if Quanta maintains a credit rating that meets two of the following three conditions: (i) a corporate credit rating that is BBB- or higher by Standard & Poor’s Rating Services, (ii) a corporate family rating that is Baa3 or higher by Moody’s Investors Services, Inc. or (iii) a corporate credit rating that is BBB- or higher by Fitch Ratings, Inc. Quanta may be required to post letters of credit or other collateral in favor of the sureties or Quanta’s customers in the future, which would reduce the borrowing availability under its senior secured credit facility. Through March 31, 2019, Quanta had not been required to make any reimbursements to our sureties for bond-related costs. To the extent a reimbursement is required, the amount could be material. See Note 14 for additional information regarding an exercise of on-demand bonds by a customer subsequent to March 31, 2019. These performance bonds expire at various times ranging from mechanical completion of the related projects to a period extending beyond contract completion in certain circumstances, and as such a determination of maximum potential amounts outstanding requires the use of certain estimates and assumptions. Such amounts can also fluctuate from period to period based upon the mix and level of Quanta’s bonded operating activity. As of March 31, 2019, the total amount of the outstanding performance bonds was estimated to be approximately $2.5 billion. Quanta’s estimated maximum exposure as it relates to the value of the performance bonds outstanding is lowered on each bonded project as the cost to complete is reduced, and each of its commitments under the performance bonds generally extinguishes concurrently with the expiration of its related contractual obligation. The estimated cost to complete these bonded projects was approximately $839 million as of March 31, 2019. Additionally, from time to time, Quanta guarantees certain obligations and liabilities of its subsidiaries that may arise in connection with, among other things, contracts with customers, equipment lease obligations, joint venture arrangements and contractors’ licenses. These guarantees may cover all of the subsidiary’s unperformed, un-discharged and un-released obligations and liabilities under or in connection with the relevant agreement. For example, with respect to customer contracts, a guarantee may cover a variety of obligations and liabilities arising during the ordinary course of the subsidiary’s business or operations, including, among other things, warranty and breach of contract claims, third party and environmental liabilities arising from the subsidiary’s work and for which it is responsible, liquidated damages amounts, or indemnity claims. Quanta is not aware of any obligations or liabilities currently asserted under any of these guarantees that are material, individually or in the aggregate. However, to the extent a subsidiary incurs a material obligation or liability and Quanta has guaranteed the performance or payment of such liability, the recovery by a customer or other counterparty or a third party will not be limited to the assets of the subsidiary. As a result, responsibility under the guarantee could exceed the amount recoverable from the subsidiary alone and could materially and adversely affect Quanta’s consolidated business, financial condition, results of operations and cash flows. Employment Agreements Quanta has various employment agreements with certain executives and other employees, which provide for compensation, other benefits and, under certain circumstances, severance payments and post-termination equity-related benefits. Certain employment agreements also contain clauses that become effective upon a change in control of Quanta, and Quanta may be obligated to pay certain amounts to such employees upon the occurrence of any of the defined change in control events. Collective Bargaining Agreements Some of Quanta’s operating units are parties to various collective bargaining agreements with unions that represent certain of their employees. The collective bargaining agreements expire at various times and have typically been renegotiated and renewed on terms similar to those in the expiring agreements. From time to time, Quanta is a party to grievance actions based on claims arising out of the collective bargaining agreements. The agreements require the operating units to pay specified wages, provide certain benefits to their union employees and contribute certain amounts to multiemployer pension plans and employee benefit trusts. Quanta’s multiemployer pension plan contribution rates generally are specified in the collective bargaining agreements (usually on an annual basis), and contributions are made to the plans on a “pay-as-you-go” basis based on its union employee payrolls. The location and number of union employees that Quanta employs at any given time and the plans in which they may participate vary depending on the projects Quanta has ongoing at any time and the need for union resources in connection with those projects. Therefore, Quanta is unable to accurately predict its union employee payroll and the amount of the resulting multiemployer pension plan contribution obligations for future periods. The Pension Protection Act of 2006 also added special funding and operational rules generally applicable to plan years beginning after 2007 for multiemployer plans that are classified as “endangered,” “seriously endangered” or “critical” status based on multiple factors (including, for example, the plan’s funded percentage, cash flow position and whether it is projected to experience a minimum funding deficiency). Plans in these classifications must adopt measures to improve their funded status through a funding improvement or rehabilitation plan, as applicable, which may require additional contributions from employers (which may take the form of a surcharge on benefit contributions) and/or modifications to retiree benefits. Certain plans to which Quanta contributes or may contribute in the future are in “endangered,” “seriously endangered” or “critical” status. The amount of additional funds, if any, that Quanta may be obligated to contribute to these plans in the future cannot be reasonably estimated due to uncertainty of the future levels of work that require the specific use of union employees covered by these plans, as well as the future contribution levels and possible surcharges on contributions applicable to these plans. Quanta may be subject to additional liabilities imposed by law as a result of its participation in multiemployer defined benefit pension plans. For example, the Employee Retirement Income Security Act of 1974, as amended by the Multiemployer Pension Plan Amendments Act of 1980, imposes certain liabilities upon an employer who is a contributor to a multiemployer pension plan if the employer withdraws from the plan or the plan is terminated or experiences a mass withdrawal. These liabilities include an allocable share of the unfunded vested benefits in the plan for all plan participants, not merely the benefits payable to a contributing employer’s own retirees. As a result, participating employers may bear a higher proportion of liability for unfunded vested benefits if other participating employers cease to contribute or withdraw, with the reallocation of liability being more acute in cases when a withdrawn employer is insolvent or otherwise fails to pay its withdrawal liability. Quanta is not aware of any material amounts of withdrawal liability that have been incurred or asserted and that remain outstanding as a result of a withdrawal by Quanta from a multiemployer defined benefit pension plan. Indemnities Quanta generally indemnifies its customers for the services it provides under its contracts, as well as other specified liabilities, which may subject Quanta to indemnity claims and liabilities and related litigation. Additionally, in connection with certain acquisitions and dispositions, Quanta has indemnified various parties against specified liabilities that those parties might incur in the future. The indemnities under acquisition or disposition agreements are usually contingent upon the other party incurring liabilities that reach specified thresholds. As of March 31, 2019, except as otherwise set forth above in Legal Proceedings, Quanta does not believe any material liabilities for claims exist against it in connection with any of these indemnity obligations. In the normal course of Quanta’s acquisition transactions, Quanta obtains rights to indemnification from the sellers or former owners of acquired businesses for certain risks, liabilities and obligations arising from their prior operations, such as performance, operational, safety, workforce or tax issues, some of which Quanta may not have discovered during due diligence. However, the indemnities may not cover all of Quanta’s exposure for such pre-acquisition matters, and the indemnitors may be unwilling or unable to pay the amounts owed to Quanta. Accordingly, Quanta may incur expenses for which it is not reimbursed. Quanta is currently in the process of negotiating certain pre-acquisition obligations associated with non-U.S. payroll taxes that may be due from a business acquired by Quanta in 2013. As of March 31, 2019, Quanta had recorded $7.4 million as its estimate of the pre-acquisition tax obligations and a corresponding indemnification asset, as management expects to recover from the indemnity counterparties any amounts that Quanta may be required to pay in connection with any such obligations.

As described in Note 9, Quanta holds investments in various entities, including joint venture entities that provide infrastructure services under specific customer contracts and partially owned entities that own and operate certain infrastructure assets constructed by Quanta. Losses incurred by these entities are generally shared ratably based on the percentage ownership of the participants in these structures. However, in Quanta’s joint venture structures that provide infrastructure services, each participant is typically jointly and severally liable for all of the obligations of the joint venture entity pursuant to the contract with the customer, as a general partner or through a parent guarantee and, therefore, can be liable for full performance of the contract with the customer. In circumstances where Quanta’s participation in a joint venture qualifies as a general partnership, the joint venture partners are jointly and severally liable for all of the obligations of the joint venture, including obligations owed to the customer or any other person or entity. Quanta is not aware of circumstances that would lead to future claims against it for material amounts in connection with these joint and several liabilities.

Additionally, in the joint venture structures entered into by Quanta, typically each party indemnifies the other party for any liabilities incurred in excess of the liabilities such other party is obligated to bear under the respective joint venture agreement or in accordance with the scope of work subcontracted to each party. It is possible, however, that Quanta could be required to pay or perform obligations in excess of its share if the other party is unable or refuses to pay or perform its share of the obligations. Quanta is not aware of circumstances that would lead to future claims against it for material amounts that would not be indemnified.

As described in Note 2, Quanta has also formed a partnership with select infrastructure investors that provides up to $1.0 billion of capital, including approximately $80.0 million from Quanta, available to invest in certain specified infrastructure projects through August 2024. As of March 31, 2019, Quanta had contributed $15.1 million to this partnership in connection with certain investments and the payment of management fees.

During 2014, a limited partnership in which Quanta is a partner was selected for an engineering, procurement and construction (EPC) electric transmission project in Canada to construct approximately 500 kilometers of transmission line and two 500 kV substations. A subsidiary of Quanta, engaged by the limited partnership, is contracted to provide turnkey EPC services for the entire project. As of March 31, 2019, Quanta made aggregate contributions to this unconsolidated affiliate of $88.7 million, received $60.6 million as a return of capital and had no outstanding additional capital commitments associated with this project.

Quanta has capital commitments for the expansion of its vehicle fleet in order to accommodate manufacturer lead times on certain types of vehicles. As of March 31, 2019, Quanta had $44.0 million of production orders with expected delivery dates in 2019. Although Quanta has committed to purchase these vehicles at the time of their delivery, Quanta anticipates that the majority of these orders will be assigned to third party leasing companies and made available under certain master equipment lease agreements, thereby releasing Quanta from its capital commitments.

Quanta is from time to time party to various lawsuits, claims and other legal proceedings that arise in the ordinary course of business. These actions typically seek, among other things, compensation for alleged personal injury, breach of contract and/or property damages, employment-related damages, punitive damages, civil penalties or other losses, or injunctive or declaratory relief. With respect to all such lawsuits, claims and proceedings, Quanta records a reserve when it is probable that a liability has been incurred and the amount of loss can be reasonably estimated. In addition, Quanta discloses matters for which management believes a material loss is at least reasonably possible. Except as otherwise stated below, none of these proceedings are expected to have a material adverse effect on Quanta’s consolidated financial position, results of operations or cash flows. In all instances, management has assessed the matter based on current information and made a judgment concerning its potential outcome, giving due consideration to the nature of the claim, the amount and nature of damages sought and the probability of success. Management’s judgment may prove materially inaccurate, and such judgment is made subject to the known uncertainties of litigation.

Maurepas Project Dispute. During the third quarter of 2017, Maurepas Pipeline, LLC (Maurepas) notified QPS Engineering, LLC (QPS), a subsidiary of Quanta, of Maurepas’ assertion of a claim for liquidated damages allegedly arising from delay in mechanical completion of a project in Louisiana. Quanta disputes the claim and believes that QPS is not responsible for liquidated damages under the contract terms. The matter remains subject to contractual dispute resolution measures; however, either party may choose to institute a formal legal proceeding upon completion of such measures. If, upon final resolution of this matter, Quanta is unsuccessful, any such liquidated damages would be recorded as additional costs on the project. As of March 31, 2019, Quanta had recorded an accrual with respect to this matter based on the current estimated amount of probable loss and believes that the range of any additional reasonably possible loss would be the difference between the accrued amount and $22.0 million, which is the maximum liability for liquidated damages pursuant to the contract terms. In July and August 2018, Quanta also received notice from Maurepas claiming certain warranty defects on the project. Quanta is evaluating the claimed defects, and based on information currently available, no estimate of reasonably possible loss related to the warranty claim can be determined.

Lorenzo Benton v. Telecom Network Specialists, Inc., et al. In June 2006, plaintiff Lorenzo Benton filed a class action complaint in the Superior Court of California, County of Los Angeles, alleging various wage and hour violations against Telecom Network Specialists (TNS), a former subsidiary of Quanta. Quanta retained liability associated with this matter pursuant to the terms of Quanta’s sale of TNS in December 2012. Benton represents a class of workers that includes all persons who worked on certain TNS projects, including individuals that TNS retained through numerous staffing agencies. The plaintiff class in this matter is seeking damages for unpaid wages, penalties associated with the failure to provide meal and rest periods and overtime wages, interest and attorneys’ fees. In January 2017, the trial court granted a summary judgment motion filed by the plaintiff class and found that TNS was a joint employer of the class members and that it failed to provide adequate meal and rest breaks and failed to pay overtime wages. In February 2019, the court granted, in part, the plaintiff class’s final motion for summary judgment on damages awarding the class approximately $7.5 million for its meal/rest break and overtime claims, and denied the motion as to penalties. Quanta believes the court’s decisions on liability and damages are not supported by controlling law and continues to contest its liability and the damage calculation asserted by the plaintiff class in this matter.

Additionally, in November 2007, TNS filed cross complaints for indemnity and breach of contract against the staffing agencies, which employed many of the individuals in question. In December 2012, the trial court heard cross-motions for summary judgment filed by TNS and the staffing agencies pertaining to TNS’s demand for indemnity. The court denied TNS’s motion and granted the motions filed by the staffing agencies; however, the California Appellate Court reversed the trial court’s decision in part and instructed the trial court to reconsider its ruling. In February 2017, the court denied a new motion for summary judgment

The final amount of liability, if any, payable in connection with this matter remains the subject of pending litigation and will ultimately depend on various factors, including the outcome of Quanta’s appeal of the trial court’s rulings on liability and damages, the final determination with respect to any additional damages owed by Quanta, and the solvency of the staffing agencies. Based on review and analysis of the trial court’s rulings on liability, Quanta does not believe, at this time, that it is probable this matter will result in a material loss. However, if Quanta is unsuccessful in this litigation and the staffing agencies are unable to fund damages owed to class members, Quanta believes the range of reasonably possible loss to Quanta upon final resolution of this matter could be up to approximately $11.0 million, plus attorneys’ fees and expenses of the plaintiff class.

Quanta is subject to concentrations of credit risk related primarily to its cash and cash equivalents and its net receivable position with customers, which includes amounts related to billed and unbilled accounts receivable and contract assets net of advanced billings with the same customer. Substantially all of Quanta’s cash and cash equivalents are managed by what it believes to be high credit quality financial institutions. In accordance with Quanta’s investment policies, these institutions are authorized to invest cash and cash equivalents in a diversified portfolio of what Quanta believes to be high quality cash and cash equivalent investments, which consist primarily of interest-bearing demand deposits, money market investments and money market mutual funds. Although Quanta does not currently believe the principal amount of these cash and cash equivalents is subject to any material risk of loss, changes in economic conditions could impact the interest income Quanta receives from these investments. In addition, Quanta grants credit under normal payment terms, generally without collateral, to its customers, which include electric power and energy companies, governmental entities, general contractors, and builders, owners and managers of commercial and industrial properties located primarily in the United States, Canada, Australia and Latin America. Consequently, Quanta is subject to potential credit risk related to changes in business and economic factors throughout these locations, which may be heightened as a result of uncertain economic and financial market conditions that have existed in recent years. However, Quanta generally has certain statutory lien rights with respect to services provided. Some of Quanta’s customers have experienced significant financial difficulties (including bankruptcy), and customers may experience financial difficulties in the future. These difficulties expose Quanta to increased risk related to collectability of billed and unbilled receivables and contract assets for services Quanta has performed.

On January 29, 2019, one of Quanta’s largest customers, PG&E, filed for bankruptcy protection under Chapter 11 of the U.S. Bankruptcy Code, as amended. Quanta is monitoring the bankruptcy proceeding and evaluating the treatment of, and potential claims related to, its pre-petition receivables. As of the bankruptcy filing date, Quanta had approximately $157 million of billed and unbilled receivables, which remained unpaid as of March 31, 2019. Subsequent to March 31, 2019, the bankruptcy court approved the assumption by PG&E of two substantial contracts with a subsidiary of Quanta, which authorizes PG&E to pay approximately $116 million of pre-petition receivables due under those contracts. As a result of the contract assumptions, Quanta expects to receive payment of the $116 million in the near term. Quanta also believes it will ultimately collect the remaining approximately $41 million of pre-petition receivables, and that amount has been classified as non-current within “Other assets, net” in the accompanying condensed consolidated balance sheet as of March 31, 2019. However, the ultimate outcome of the bankruptcy proceeding is uncertain, and Quanta’s belief regarding collection of the remaining receivables is based on a number of assumptions that are potentially subject to change as the proceeding progresses. Should any of those assumptions change, the amount collected could be materially less than the amount of the remaining receivables. Additionally, Quanta is continuing to perform services for PG&E while the bankruptcy case is ongoing and believes that amounts billed for post-petition services will continue to be collected in the ordinary course of business.

As discussed in Note 2, Quanta is insured for employer’s liability, workers’ compensation, auto liability, general liability and group health claims. As of March 31, 2019 and December 31, 2018, the gross amount accrued for insurance claims totaled $268.7 million and $272.9 million, with $200.8 million and $210.1 million considered to be long-term and included in “Insurance and other non-current liabilities.” Related insurance recoveries/receivables as of March 31, 2019 and December 31, 2018 were $35.8 million and $56.5 million, of which $0.4 million and $0.3 million were included in “Prepaid expenses and other current assets” and $35.4 million and $56.2 million were included in “Other assets, net.”

Project Insurance Claim. In June 2018, while performing a horizontal directional drill and installing an underground gas pipeline, one of Quanta’s subsidiaries experienced a partial collapse of a borehole. Subsequent to the incident, Quanta has been working with its customer to mitigate the impact of the incident and to complete the project; however, Quanta has encountered additional challenges due to the collapsed borehole. As required by the contract, the customer procured certain insurance coverage for the project, with the Quanta subsidiary as an additional insured. Quanta believes the incident is covered under such insurance and is working collaboratively with the customer to pursue insurance claims with the customer’s insurance carriers. To the extent such claims are not successful, Quanta would expect to pursue contractual relief from the customer.

As of March 31, 2019, Quanta had recorded an insurance receivable of $45.8 million in accordance with GAAP related to accounting for insurance claims and potential recoveries. The amount represents a portion of the insurance claims being pursued as of such date. Quanta expects the insurance claims and the amount of the insurance receivable to increase in future periods as mitigation activities continue. The mitigation plan remains subject to inherent risks associated with underground pipeline installation, which could cause the costs to mitigate the incident to increase materially. The project is ongoing and the final amount of the insurance claims is not currently known. However, Quanta’s claims associated with the project, including both insurance claims and potential contractual claims, will be substantially in excess of the currently recognized receivable. To the extent Quanta is unsuccessful in realizing insurance or contractual recoveries, additional charges to operating results, which could be material, would be required.

Certain of Quanta’s vendors require letters of credit to ensure reimbursement for amounts they are disbursing on Quanta’s behalf, such as to beneficiaries under its insurance programs. In addition, from time to time, certain customers require Quanta to post letters of credit to ensure payment of subcontractors and vendors and guarantee performance under contracts. Such letters of credit are generally issued by a bank or similar financial institution, typically pursuant to Quanta’s senior secured credit facility. Each letter of credit commits the issuer to pay specified amounts to the holder of the letter of credit if the holder claims that Quanta has failed to perform specified actions. If this were to occur, Quanta would be required to reimburse the issuer of the letter of credit. Depending on the circumstances of such a reimbursement, Quanta may also be required to record a charge to earnings for the reimbursement. Quanta does not believe it is likely that any material claims will be made under a letter of credit in the foreseeable future.

As of March 31, 2019, Quanta had $385.0 million in outstanding letters of credit and bank guarantees under its senior secured credit facility securing its casualty insurance program and various contractual commitments. These are irrevocable stand-by letters of credit with maturities generally expiring at various times throughout 2019 and 2020. Quanta expects to renew the majority of the letters of credit related to the casualty insurance program for subsequent one-year periods upon maturity.

Many customers, particularly in connection with new construction, require Quanta to post performance and payment bonds issued by a financial institution known as a surety. These bonds provide a guarantee to the customer that Quanta will perform under the terms of a contract and pay its subcontractors and vendors. If Quanta fails to perform, the customer may demand that the surety make payments or provide services under the bond. Quanta must reimburse the surety for any expenses or outlays it incurs. Under Quanta’s underwriting, continuing indemnity and security agreement with its sureties and with the consent of the lenders that are party to Quanta’s credit agreement, Quanta has granted security interests in certain of our assets as collateral for its obligations to the sureties. Subject to certain conditions and consistent with terms of Quanta’s credit agreement, these security interests will be automatically released if Quanta maintains a credit rating that meets two of the following three conditions: (i) a corporate credit rating that is BBB- or higher by Standard & Poor’s Rating Services, (ii) a corporate family rating that is Baa3 or higher by Moody’s Investors Services, Inc. or (iii) a corporate credit rating that is BBB- or higher by Fitch Ratings, Inc. Quanta may be required to post letters of credit or other collateral in favor of the sureties or Quanta’s customers in the future, which would reduce the borrowing availability under its senior secured credit facility. Through March 31, 2019, Quanta had not been required to make any reimbursements to our sureties for bond-related costs. To the extent a reimbursement is required, the amount could be material. See Note 14 for additional information regarding an exercise of on-demand bonds by a customer subsequent to March 31, 2019.

These performance bonds expire at various times ranging from mechanical completion of the related projects to a period extending beyond contract completion in certain circumstances, and as such a determination of maximum potential amounts outstanding requires the use of certain estimates and assumptions. Such amounts can also fluctuate from period to period based upon the mix and level of Quanta’s bonded operating activity. As of March 31, 2019, the total amount of the outstanding performance bonds was estimated to be approximately $2.5 billion. Quanta’s estimated maximum exposure as it relates to the value of the

Additionally, from time to time, Quanta guarantees certain obligations and liabilities of its subsidiaries that may arise in connection with, among other things, contracts with customers, equipment lease obligations, joint venture arrangements and contractors’ licenses. These guarantees may cover all of the subsidiary’s unperformed, un-discharged and un-released obligations and liabilities under or in connection with the relevant agreement. For example, with respect to customer contracts, a guarantee may cover a variety of obligations and liabilities arising during the ordinary course of the subsidiary’s business or operations, including, among other things, warranty and breach of contract claims, third party and environmental liabilities arising from the subsidiary’s work and for which it is responsible, liquidated damages amounts, or indemnity claims. Quanta is not aware of any obligations or liabilities currently asserted under any of these guarantees that are material, individually or in the aggregate. However, to the extent a subsidiary incurs a material obligation or liability and Quanta has guaranteed the performance or payment of such liability, the recovery by a customer or other counterparty or a third party will not be limited to the assets of the subsidiary. As a result, responsibility under the guarantee could exceed the amount recoverable from the subsidiary alone and could materially and adversely affect Quanta’s consolidated business, financial condition, results of operations and cash flows.

Quanta has various employment agreements with certain executives and other employees, which provide for compensation, other benefits and, under certain circumstances, severance payments and post-termination equity-related benefits. Certain employment agreements also contain clauses that become effective upon a change in control of Quanta, and Quanta may be obligated to pay certain amounts to such employees upon the occurrence of any of the defined change in control events.

Some of Quanta’s operating units are parties to various collective bargaining agreements with unions that represent certain of their employees. The collective bargaining agreements expire at various times and have typically been renegotiated and renewed on terms similar to those in the expiring agreements. From time to time, Quanta is a party to grievance actions based on claims arising out of the collective bargaining agreements. The agreements require the operating units to pay specified wages, provide certain benefits to their union employees and contribute certain amounts to multiemployer pension plans and employee benefit trusts. Quanta’s multiemployer pension plan contribution rates generally are specified in the collective bargaining agreements (usually on an annual basis), and contributions are made to the plans on a “pay-as-you-go” basis based on its union employee payrolls. The location and number of union employees that Quanta employs at any given time and the plans in which they may participate vary depending on the projects Quanta has ongoing at any time and the need for union resources in connection with those projects. Therefore, Quanta is unable to accurately predict its union employee payroll and the amount of the resulting multiemployer pension plan contribution obligations for future periods.

The Pension Protection Act of 2006 also added special funding and operational rules generally applicable to plan years beginning after 2007 for multiemployer plans that are classified as “endangered,” “seriously endangered” or “critical” status based on multiple factors (including, for example, the plan’s funded percentage, cash flow position and whether it is projected to experience a minimum funding deficiency). Plans in these classifications must adopt measures to improve their funded status through a funding improvement or rehabilitation plan, as applicable, which may require additional contributions from employers (which may take the form of a surcharge on benefit contributions) and/or modifications to retiree benefits. Certain plans to which Quanta contributes or may contribute in the future are in “endangered,” “seriously endangered” or “critical” status. The amount of additional funds, if any, that Quanta may be obligated to contribute to these plans in the future cannot be reasonably estimated due to uncertainty of the future levels of work that require the specific use of union employees covered by these plans, as well as the future contribution levels and possible surcharges on contributions applicable to these plans.

Quanta may be subject to additional liabilities imposed by law as a result of its participation in multiemployer defined benefit pension plans. For example, the Employee Retirement Income Security Act of 1974, as amended by the Multiemployer Pension Plan Amendments Act of 1980, imposes certain liabilities upon an employer who is a contributor to a multiemployer pension plan if the employer withdraws from the plan or the plan is terminated or experiences a mass withdrawal. These liabilities include an allocable share of the unfunded vested benefits in the plan for all plan participants, not merely the benefits payable to a contributing employer’s own retirees. As a result, participating employers may bear a higher proportion of liability for unfunded vested benefits if other participating employers cease to contribute or withdraw, with the reallocation of liability being more acute in cases when a withdrawn employer is insolvent or otherwise fails to pay its withdrawal liability. Quanta is not aware of any material amounts of withdrawal liability that have been incurred or asserted and that remain outstanding as a result of a withdrawal by Quanta from

Quanta generally indemnifies its customers for the services it provides under its contracts, as well as other specified liabilities, which may subject Quanta to indemnity claims and liabilities and related litigation. Additionally, in connection with certain acquisitions and dispositions, Quanta has indemnified various parties against specified liabilities that those parties might incur in the future. The indemnities under acquisition or disposition agreements are usually contingent upon the other party incurring liabilities that reach specified thresholds. As of March 31, 2019, except as otherwise set forth above in Legal Proceedings, Quanta does not believe any material liabilities for claims exist against it in connection with any of these indemnity obligations.