Business and Organization, Basis of Presentation and Accounting Policies (Policies)	3 Months Ended
Mar. 31, 2025
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Interim Condensed Consolidated Financial Information	These unaudited condensed consolidated financial statements have been prepared in accordance with the instructions to Form 10-Q and Rule 10-01 of Regulation S-X for interim financial information. Certain information and footnote disclosures, normally included in annual financial statements prepared in accordance with generally accepted accounting principles in the United States (GAAP), have been condensed or omitted pursuant to those rules and regulations. These unaudited condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements and notes thereto of Quanta’s Annual Report on Form 10-K for the year ended December 31, 2024. Quanta believes that the disclosures made are adequate to make the information presented not misleading. In the opinion of management, all adjustments, consisting only of normal recurring adjustments, necessary to fairly state the financial position, results of operations, comprehensive income and cash flows with respect to the interim condensed consolidated financial statements have been included. The results of Quanta have historically been subject to seasonal fluctuations. The results of operations, comprehensive income and operating cash flows for the interim periods are not necessarily indicative of the results for the entire fiscal year.
Recently Adopted Guidance and New Accounting Pronouncements and Disclosure Rules Not Yet Adopted	New Accounting Pronouncements and Disclosure Rules Not Yet Adopted In November 2024, the FASB issued an update that requires incremental disclosures about specific expense categories. Entities are required to disclose in the notes to financial statements the amounts of purchases of inventory, employee compensation, depreciation, intangible asset amortization and selling expense included in each relevant expense caption of the statements of operations. The standard also requires disclosure of the amount, and a qualitative description of, other items remaining in relevant expense captions that are not separately disaggregated. This update is effective for fiscal years beginning after December 15, 2026, and interim periods within fiscal years beginning after December 15, 2027. Early adoption and both prospective and retrospective application are permitted. Quanta is currently assessing the effect of this update. In December 2023, the FASB issued an update that expands disclosures for tax rate reconciliation tables, primarily by requiring disaggregation of income taxes paid by jurisdiction, as well as greater disaggregation within the rate reconciliation. This update is effective for fiscal years beginning after December 15, 2024 and interim periods within fiscal years beginning after December 15, 2025. Early adoption and retrospective application are permitted. Quanta is currently assessing the effect of this update.
Revenue Recognition	Contracts Quanta’s services are generally provided pursuant to master service agreements (MSAs), repair and maintenance contracts and fixed price and non-fixed price construction contracts. Contracts are combined if they are entered into at or near the same time as one another and negotiated as a group, in contemplation of one another, for a related commercial purpose. When applicable, the transaction price is allocated to performance obligations on the basis of relative standalone selling prices that is generally determined using an expected profit margin on anticipated costs related to the performance obligation. Quanta’s contracts are classified into three categories: unit-price contracts, cost-plus contracts and fixed price contracts.Under fixed-price contracts, as well as unit-price contracts with more than an insignificant amount of partially completed units, revenue is recognized as performance obligations are satisfied over time, with the percentage of completion generally measured as the percentage of costs incurred to total estimated costs for such performance obligation.These amounts represent management’s estimates of the consolidated revenues that are expected to be realized from the remaining portion of firm orders under fixed price contracts not yet completed or for which work had not yet begun as of such dates and, to a lesser extent, from certain unit-price contracts with more than an insignificant amount of partially completed units. For purposes of calculating remaining performance obligations, Quanta includes all estimated revenues attributable to consolidated joint ventures and variable interest entities, revenues from funded and unfunded portions of government contracts to the extent they are reasonably expected to be realized, and revenues from change orders and claims to the extent management believes additional contract revenues will be earned and are deemed probable of collection. Excluded from remaining performance obligations are potential orders under MSAs and expected revenues under certain non-fixed price contracts. Contract Estimates and Changes in Estimates Actual revenues and project costs can vary, sometimes substantially, from previous estimates due to changes in a variety of factors, including unforeseen or changed circumstances not included in Quanta’s cost estimates or covered by its contracts. Some of the factors that can result in positive changes in estimates on projects include successful execution through project risks, reduction of estimated project costs or increases of estimated revenues. Some of the factors that can result in negative changes in estimates include concealed or unknown site conditions; changes to or disputes with customers regarding the scope of services; changes in estimates related to the length of time to complete a performance obligation; changes or delays with respect to permitting and regulatory requirements and materials; changes in the cost of equipment, commodities, materials or skilled labor; unanticipated costs or claims due to delays or failure to perform by customers or third parties; customer failure to provide, or supply chain and logistical challenges related to, required materials or equipment; errors in engineering, specifications or designs; project modifications; adverse weather conditions, natural disasters, and other emergencies; and performance and quality issues causing delay (including payment of liquidated damages) or requiring rework or replacement. Any changes in estimates could result in changes to profitability or losses associated with the related performance obligations. Additionally, changes in cost estimates on certain contracts may result in the issuance of change orders, which can be approved or unapproved by the customer, or the assertion of contract claims. Quanta recognizes amounts associated with change orders and claims as revenue if it is probable that the contract price will be adjusted and the amount of any such adjustment can be reasonably estimated. Changes in estimates can result in the recognition of revenue in a current period for performance obligations that were satisfied or partially satisfied in prior periods or the reversal of previously recognized revenue if the currently estimated revenue is less than the previous estimate. The impact of a change in contract estimate is measured as the difference between the revenue or gross profit recognized in the prior period as compared to the revenue or gross profit which would have been recognized had the revised estimate been used as the basis of recognition in the prior period. Changes in estimates can also result in contract losses, which are recognized in full when they are determined to be probable and can be reasonably estimated. Quanta determines its allowance for credit losses based on an estimate of expected credit losses for financial instruments, primarily accounts receivable and contract assets. The assessment of the allowance for credit losses involves certain judgments and estimates. Management estimates the allowance balance using relevant available information from internal and external sources relating to past events, current conditions and reasonable and supportable forecasts. Expected credit losses are estimated by evaluating trends with respect to Quanta’s historical write-off experience and applying historical loss ratios to pools of financial assets with similar risk characteristics. Quanta has determined that it has two risk pools for the purpose of calculating its historical credit loss experience. Quanta’s historical loss ratio and its determination of risk pools, which are used to calculate expected credit losses, may be adjusted for changes in customer credit concentrations within its portfolio of financial assets, changes in customers’ ability to pay, and other considerations, such as economic and market changes, changes to regulatory or technological environments affecting customers and the consistency between current and forecasted economic conditions and the historical economic conditions used to derive historical loss ratios. At the end of each quarter, management reassesses these and other relevant factors, including the impact of uncertainty and challenges in the overall economy and in Quanta’s industries and markets, (e.g., inflationary pressure, supply chain and other logistical challenges and increased interest rates). Additional allowance for credit losses is established for financial asset balances with specific customers where collectability has been determined to be improbable based on customer specific facts and circumstances. Quanta considers accounts receivable delinquent after 30 days but, absent certain specific considerations, generally does not consider such amounts delinquent in its credit loss analysis unless the accounts receivable are at least 120 days outstanding. In addition, management monitors the credit quality of its receivables by, among other things, obtaining credit ratings for significant customers, assessing economic and market conditions and evaluating material changes to a customer’s business, cash flows and financial condition. Should anticipated recoveries relating to receivables fail to materialize, including anticipated recoveries relating to bankruptcies or other workout situations, Quanta could experience reduced cash flows and losses in excess of current allowances provided. Accounts receivable are written-off against the allowance for credit losses if they are deemed uncollectible. Quanta recognizes unbilled receivables for non-fixed price contracts within “Accounts receivable” in certain circumstances, such as when revenues have been earned and recorded but the amount cannot be billed under the terms of the contract until a later date or when amounts arise from routine lags in billing. These balances do not include revenues recognized for work performed under fixed-price contracts and unit-price contracts with more than an insignificant amount of partially completed units, as these amounts are recorded as “Contract assets.” As of March 31, 2025 and December 31, 2024, unbilled receivables included in “Accounts receivable” were $946.2 million and $859.9 million. Quanta also recognizes unearned revenues for non-fixed price contracts when cash is received prior to recognizing revenues for the related performance obligation. Unearned revenues, which are included in “Accounts payable and accrued expenses,” were $82.9 million and $97.9 million as of March 31, 2025 and December 31, 2024.
Segment Information	Quanta’s operations are managed by senior executives who report to its Chief Executive Officer, the chief operating decision maker. The Chief Executive Officer uses operating income for each of Quanta’s reportable segments and considers forecast to actual variances to assess performance and when making decisions about allocating capital, craft skill labor and other resources. During the three months ending March 31, 2025, Quanta’s Chief Executive Officer reevaluated how performance of the business is assessed and how resources are allocated, which resulted in a change in the reporting of management’s internal financial information. As a result, beginning with the three months ended March 31, 2025, Quanta began reporting the results of its two operating segments, which are also its two reportable segments: (1) Electric Infrastructure Solutions (Electric) and (2) Underground Utility and Infrastructure Solutions (Underground and Infrastructure). The Electric segment consists of the historical Electric Power Infrastructure Solutions and the Renewable Energy Infrastructure Solutions segments. In conjunction with this change, certain prior period amounts have been recast to conform to this new segment reporting structure. Electric. Quanta’s Electric segment provides comprehensive services for the electric power, renewable energy, technology and communications markets. Services include, but are not limited to, the design, procurement, new construction, upgrade and repair and maintenance services for electric power transmission and distribution infrastructure, both overhead and underground, and substation facilities, along with other engineering and technical services, including services that support the implementation of upgrades by utilities to modernize and harden the electric power grid in order to ensure its safety and enhance reliability, to interconnect and transmit electricity from renewable energy generation and battery storage facilities and to accommodate increased residential and commercial use of electric vehicles. In addition, this segment provides engineering, procurement, new construction, repowering and repair and maintenance services for renewable generation facilities, such as utility-scale wind, solar and hydropower generation facilities and battery storage facilities, as well as emergency restoration services, including the repair of infrastructure damaged by fire and inclement weather and the installation of “smart grid” technologies on electric power networks. This segment also provides comprehensive design and construction solutions to wireline and wireless communications companies; electrical systems for technology, commercial and industrial facilities and other load centers, commercial and industrial facilities; and cable multi-system operators and other customers within the communications industry, as well as other related services. Additionally, this segment manufactures power transformers and components for the electric utility, renewable energy, municipal power and industrial markets. Underground and Infrastructure. Quanta’s Underground and Infrastructure segment provides comprehensive infrastructure solutions to customers involved in the transportation, distribution, storage, development and processing of natural gas, oil and other products. Services include, but are not limited to design, engineering, procurement, new construction, upgrade and repair and maintenance services for natural gas systems for gas utility customers; pipeline construction, protection, integrity testing, rehabilitation and replacement services; and civil solutions. Additionally, Quanta serves the midstream and downstream industrial energy markets through catalyst replacement services, high-pressure and critical-path turnaround services, instrumentation and electrical services, piping, fabrication and storage tank services. Quanta’s segment results are derived from the types of services provided across its operating companies in each of its end user markets. Quanta’s entrepreneurial business model allows multiple operating companies to serve the same or similar customers and to provide a range of services across end user markets. Reportable segment information, including revenues and operating income by type of work, is gathered from each operating company. Classification of operating company revenues by type of work for segment reporting purposes can require judgment on the part of management. Segment operating expenses (excluding depreciation expense) primarily includes cost of services, such as wages and benefits; subcontractor costs; materials; certain equipment rental and maintenance costs, and other direct and indirect project costs, as well as allocated segment selling, general and administrative expenses. Integrated operations and common administrative support for Quanta’s operating companies require that allocations be made to determine segment profitability, including allocations of certain corporate shared and indirect operating costs as well as general and administrative costs. Separate measures of Quanta’s assets and cash flows by reportable segment, including capital expenditures, are not produced or utilized by the Chief Executive Officer to evaluate segment performance since certain of Quanta’s fixed assets are used on an interchangeable basis across its reportable segments. As such, for reporting purposes, total depreciation expense is determined quarterly by allocating depreciation expense at each legal entity to Quanta’s reportable segments based on the ratio of each legal entity’s revenue contribution to each of Quanta’s segments. Corporate and non-allocated costs include corporate facility costs; non-allocated corporate salaries, benefits and incentive compensation; acquisition and integration costs; non-cash stock-based compensation; amortization related to intangible assets; asset impairment related to goodwill and intangible assets; and change in fair value of contingent consideration liabilities.
Income Taxes	Quanta regularly evaluates valuation allowances established for deferred tax assets (DTAs) for which future realization is uncertain, including in connection with changes in tax laws. The estimation of required valuation allowances includes estimates of future taxable income. The ultimate realization of DTAs is dependent upon the generation of future taxable income in the jurisdiction of the DTAs during the periods in which those temporary differences become deductible. Quanta considers projected future taxable income and tax planning strategies in making this assessment. If actual future taxable income differs from these estimates, Quanta may not realize DTAs to the extent estimated.
Cash and Cash Equivalents	Cash and cash equivalents held by joint ventures, which are either consolidated or proportionately consolidated, are available to support joint venture operations, but Quanta cannot utilize those assets to support its other operations. Quanta generally has no right to cash and cash equivalents held by a joint venture other than participating in distributions, to the extent made, and in the event of dissolution. Cash and cash equivalents held by Quanta’s wholly-owned captive insurance company are generally not available for use in support of its other operations.
Contingent Consideration Liabilities	The estimated fair values of these contingent consideration liabilities are measured on a recurring basis using a probability-weighted discounted cash flow method, which considers significant inputs not observable in the market and are Level 3 inputs.
Commitments and Contingencies	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. The assessment of whether a loss is probable or reasonably possible, and whether the loss or a range of loss is estimable, often involves a series of complex judgments about future events. 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 and taking into account, among other things, negotiations with claimants, discovery, settlements and payments, judicial rulings, arbitration and mediation decisions, advice of internal and external legal counsel, and other information and events pertaining to a particular matter. Costs incurred for litigation are expensed as incurred. 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. However, management’s judgment may prove materially inaccurate, and such judgment is made subject to the known uncertainties of litigation. Losses under these insurance programs are accrued based upon Quanta’s estimate of the ultimate liability for claims reported and an estimate of claims incurred but not reported, with assistance from third-party actuaries. These insurance liabilities are difficult to assess and estimate due to unknown factors, including the severity of an injury, the extent of damage, the determination of Quanta’s liability in proportion to other parties, the number of incidents not reported and the overall claims environment. The accruals are based upon known facts and historical trends, and management believes such accruals are adequate.

Business and Organization, Basis of Presentation and Accounting Policies (Policies)

3 Months Ended

Mar. 31, 2025

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Interim Condensed Consolidated Financial Information

These unaudited condensed consolidated financial statements have been prepared in accordance with the instructions to Form 10-Q and Rule 10-01 of Regulation S-X for interim financial information. Certain information and footnote disclosures, normally included in annual financial statements prepared in accordance with generally accepted accounting principles in the United States (GAAP), have been condensed or omitted pursuant to those rules and regulations. These unaudited condensed consolidated financial statements should be read in conjunction with the audited consolidated financial statements and notes thereto of Quanta’s Annual Report on Form 10-K for the year ended December 31, 2024. Quanta believes that the disclosures made are adequate to make the information presented not misleading. In the opinion of management, all adjustments, consisting only of normal recurring adjustments, necessary to fairly state the financial position, results of operations, comprehensive income and cash flows with respect to the interim condensed consolidated financial statements have been included.

The results of Quanta have historically been subject to seasonal fluctuations. The results of operations, comprehensive income and operating cash flows for the interim periods are not necessarily indicative of the results for the entire fiscal year.

Recently Adopted Guidance and New Accounting Pronouncements and Disclosure Rules Not Yet Adopted

New Accounting Pronouncements and Disclosure Rules Not Yet Adopted

In November 2024, the FASB issued an update that requires incremental disclosures about specific expense categories. Entities are required to disclose in the notes to financial statements the amounts of purchases of inventory, employee compensation, depreciation, intangible asset amortization and selling expense included in each relevant expense caption of the statements of operations. The standard also requires disclosure of the amount, and a qualitative description of, other items remaining in relevant expense captions that are not separately disaggregated. This update is effective for fiscal years beginning after December 15, 2026, and interim periods within fiscal years beginning after December 15, 2027. Early adoption and both prospective and retrospective application are permitted. Quanta is currently assessing the effect of this update.

In December 2023, the FASB issued an update that expands disclosures for tax rate reconciliation tables, primarily by requiring disaggregation of income taxes paid by jurisdiction, as well as greater disaggregation within the rate reconciliation. This update is effective for fiscal years beginning after December 15, 2024 and interim periods within fiscal years beginning after December 15, 2025. Early adoption and retrospective application are permitted. Quanta is currently assessing the effect of this update.

Revenue Recognition

Contracts

Quanta’s services are generally provided pursuant to master service agreements (MSAs), repair and maintenance contracts and fixed price and non-fixed price construction contracts. Contracts are combined if they are entered into at or near the same time as one another and negotiated as a group, in contemplation of one another, for a related commercial purpose. When applicable, the transaction price is allocated to performance obligations on the basis of relative standalone selling prices that is generally determined using an expected profit margin on anticipated costs related to the performance obligation. Quanta’s contracts are classified into three categories: unit-price contracts, cost-plus contracts and fixed price contracts.Under fixed-price contracts, as well as unit-price contracts with more than an insignificant amount of partially completed units, revenue is recognized as performance obligations are satisfied over time, with the percentage of completion generally measured as the percentage of costs incurred to total estimated costs for such performance obligation.These amounts represent management’s estimates of the consolidated revenues that are expected to be realized from the remaining portion of firm orders under fixed price contracts not yet completed or for which work had not yet begun as of such dates and, to a lesser extent, from certain unit-price contracts with more than an insignificant amount of partially completed units. For purposes of calculating remaining performance obligations, Quanta includes all estimated revenues attributable to consolidated joint ventures and variable interest entities, revenues from funded and unfunded portions of government contracts to the extent they are reasonably expected to be realized, and revenues from change orders and claims to the extent management believes additional contract revenues will be earned and are deemed probable of collection. Excluded from remaining performance obligations are potential orders under MSAs and expected revenues under certain non-fixed price contracts.

Contract Estimates and Changes in Estimates

Actual revenues and project costs can vary, sometimes substantially, from previous estimates due to changes in a variety of factors, including unforeseen or changed circumstances not included in Quanta’s cost estimates or covered by its contracts. Some of the factors that can result in positive changes in estimates on projects include successful execution through project risks, reduction of estimated project costs or increases of estimated revenues. Some of the factors that can result in negative changes in estimates include concealed or unknown site conditions; changes to or disputes with customers regarding the scope of services; changes in estimates related to the length of time to complete a performance obligation; changes or delays with respect to permitting and regulatory requirements and materials; changes in the cost of equipment, commodities, materials or skilled labor; unanticipated costs or claims due to delays or failure to perform by customers or third parties; customer failure to provide, or supply chain and logistical challenges related to, required materials or equipment; errors in engineering, specifications or designs; project modifications; adverse weather conditions, natural disasters, and other emergencies; and performance and quality issues causing delay (including payment of liquidated damages) or requiring rework or replacement. Any changes in estimates could result in changes to profitability or losses associated with the related performance obligations.

Additionally, changes in cost estimates on certain contracts may result in the issuance of change orders, which can be approved or unapproved by the customer, or the assertion of contract claims. Quanta recognizes amounts associated with change orders and claims as revenue if it is probable that the contract price will be adjusted and the amount of any such adjustment can be reasonably estimated.

Changes in estimates can result in the recognition of revenue in a current period for performance obligations that were satisfied or partially satisfied in prior periods or the reversal of previously recognized revenue if the currently estimated revenue is less than the previous estimate. The impact of a change in contract estimate is measured as the difference between the revenue or gross profit recognized in the prior period as compared to the revenue or gross profit which would have been recognized had the revised estimate been used as the basis of recognition in the prior period. Changes in estimates can also result in contract losses, which are recognized in full when they are determined to be probable and can be reasonably estimated.

Quanta determines its allowance for credit losses based on an estimate of expected credit losses for financial instruments, primarily accounts receivable and contract assets. The assessment of the allowance for credit losses involves certain judgments and estimates. Management estimates the allowance balance using relevant available information from internal and external sources relating to past events, current conditions and reasonable and supportable forecasts. Expected credit losses are estimated by evaluating trends with respect to Quanta’s historical write-off experience and applying historical loss ratios to pools of financial assets with similar risk characteristics. Quanta has determined that it has two risk pools for the purpose of calculating its historical credit loss experience.

Quanta’s historical loss ratio and its determination of risk pools, which are used to calculate expected credit losses, may be adjusted for changes in customer credit concentrations within its portfolio of financial assets, changes in customers’ ability to pay, and other considerations, such as economic and market changes, changes to regulatory or technological environments affecting customers and the consistency between current and forecasted economic conditions and the historical economic

conditions used to derive historical loss ratios. At the end of each quarter, management reassesses these and other relevant factors, including the impact of uncertainty and challenges in the overall economy and in Quanta’s industries and markets, (e.g., inflationary pressure, supply chain and other logistical challenges and increased interest rates).

Additional allowance for credit losses is established for financial asset balances with specific customers where collectability has been determined to be improbable based on customer specific facts and circumstances. Quanta considers accounts receivable delinquent after 30 days but, absent certain specific considerations, generally does not consider such amounts delinquent in its credit loss analysis unless the accounts receivable are at least 120 days outstanding. In addition, management monitors the credit quality of its receivables by, among other things, obtaining credit ratings for significant customers, assessing economic and market conditions and evaluating material changes to a customer’s business, cash flows and financial condition. Should anticipated recoveries relating to receivables fail to materialize, including anticipated recoveries relating to bankruptcies or other workout situations, Quanta could experience reduced cash flows and losses in excess of current allowances provided.

Accounts receivable are written-off against the allowance for credit losses if they are deemed uncollectible.

Quanta recognizes unbilled receivables for non-fixed price contracts within “Accounts receivable” in certain circumstances, such as when revenues have been earned and recorded but the amount cannot be billed under the terms of the contract until a later date or when amounts arise from routine lags in billing. These balances do not include revenues recognized for work performed under fixed-price contracts and unit-price contracts with more than an insignificant amount of partially completed units, as these amounts are recorded as “Contract assets.” As of March 31, 2025 and December 31, 2024, unbilled receivables included in “Accounts receivable” were $946.2 million and $859.9 million. Quanta also recognizes unearned revenues for non-fixed price contracts when cash is received prior to recognizing revenues for the related performance obligation. Unearned revenues, which are included in “Accounts payable and accrued expenses,” were $82.9 million and $97.9 million as of March 31, 2025 and December 31, 2024.

Segment Information

Quanta’s operations are managed by senior executives who report to its Chief Executive Officer, the chief operating decision maker. The Chief Executive Officer uses operating income for each of Quanta’s reportable segments and considers forecast to actual variances to assess performance and when making decisions about allocating capital, craft skill labor and other resources.

During the three months ending March 31, 2025, Quanta’s Chief Executive Officer reevaluated how performance of the business is assessed and how resources are allocated, which resulted in a change in the reporting of management’s internal financial information. As a result, beginning with the three months ended March 31, 2025, Quanta began reporting the results of its two operating segments, which are also its two reportable segments: (1) Electric Infrastructure Solutions (Electric) and (2) Underground Utility and Infrastructure Solutions (Underground and Infrastructure). The Electric segment consists of the historical Electric Power Infrastructure Solutions and the Renewable Energy Infrastructure Solutions segments. In conjunction with this change, certain prior period amounts have been recast to conform to this new segment reporting structure.

Electric. Quanta’s Electric segment provides comprehensive services for the electric power, renewable energy, technology and communications markets. Services include, but are not limited to, the design, procurement, new construction, upgrade and repair and maintenance services for electric power transmission and distribution infrastructure, both overhead and underground, and substation facilities, along with other engineering and technical services, including services that support the implementation of upgrades by utilities to modernize and harden the electric power grid in order to ensure its safety and enhance reliability, to interconnect and transmit electricity from renewable energy generation and battery storage facilities and to accommodate increased residential and commercial use of electric vehicles. In addition, this segment provides engineering, procurement, new construction, repowering and repair and maintenance services for renewable generation facilities, such as utility-scale wind, solar and hydropower generation facilities and battery storage facilities, as well as emergency restoration services, including the repair of infrastructure damaged by fire and inclement weather and the installation of “smart grid” technologies on electric power networks. This segment also provides comprehensive design and construction solutions to wireline and wireless communications companies; electrical systems for technology, commercial and industrial facilities and other load centers, commercial and industrial facilities; and cable multi-system operators and other customers within the communications industry, as well as other related services. Additionally, this segment manufactures power transformers and components for the electric utility, renewable energy, municipal power and industrial markets.

Underground and Infrastructure. Quanta’s Underground and Infrastructure segment provides comprehensive infrastructure solutions to customers involved in the transportation, distribution, storage, development and processing of natural gas, oil and other products. Services include, but are not limited to design, engineering, procurement, new construction, upgrade and repair and maintenance services for natural gas systems for gas utility customers; pipeline construction, protection, integrity testing, rehabilitation and replacement services; and civil solutions. Additionally, Quanta serves the midstream and downstream industrial energy markets through catalyst replacement services, high-pressure and critical-path turnaround services, instrumentation and electrical services, piping, fabrication and storage tank services.

Quanta’s segment results are derived from the types of services provided across its operating companies in each of its end user markets. Quanta’s entrepreneurial business model allows multiple operating companies to serve the same or similar customers and to provide a range of services across end user markets. Reportable segment information, including revenues and operating income by type of work, is gathered from each operating company. Classification of operating company revenues by type of work for segment reporting purposes can require judgment on the part of management.

Segment operating expenses (excluding depreciation expense) primarily includes cost of services, such as wages and benefits; subcontractor costs; materials; certain equipment rental and maintenance costs, and other direct and indirect project costs, as well as allocated segment selling, general and administrative expenses. Integrated operations and common administrative support for Quanta’s operating companies require that allocations be made to determine segment profitability, including allocations of certain corporate shared and indirect operating costs as well as general and administrative costs.

Separate measures of Quanta’s assets and cash flows by reportable segment, including capital expenditures, are not produced or utilized by the Chief Executive Officer to evaluate segment performance since certain of Quanta’s fixed assets are used on an interchangeable basis across its reportable segments. As such, for reporting purposes, total depreciation expense is determined quarterly by allocating depreciation expense at each legal entity to Quanta’s reportable segments based on the ratio of each legal entity’s revenue contribution to each of Quanta’s segments.

Corporate and non-allocated costs include corporate facility costs; non-allocated corporate salaries, benefits and incentive compensation; acquisition and integration costs; non-cash stock-based compensation; amortization related to intangible assets; asset impairment related to goodwill and intangible assets; and change in fair value of contingent consideration liabilities.

Income Taxes

Quanta regularly evaluates valuation allowances established for deferred tax assets (DTAs) for which future realization is uncertain, including in connection with changes in tax laws. The estimation of required valuation allowances includes estimates

of future taxable income. The ultimate realization of DTAs is dependent upon the generation of future taxable income in the jurisdiction of the DTAs during the periods in which those temporary differences become deductible. Quanta considers projected future taxable income and tax planning strategies in making this assessment. If actual future taxable income differs from these estimates, Quanta may not realize DTAs to the extent estimated.

Cash and Cash Equivalents

Cash and cash equivalents held by joint ventures, which are either consolidated or proportionately consolidated, are available to support joint venture operations, but Quanta cannot utilize those assets to support its other operations. Quanta generally has no right to cash and cash equivalents held by a joint venture other than participating in distributions, to the extent made, and in the event of dissolution. Cash and cash equivalents held by Quanta’s wholly-owned captive insurance company are generally not available for use in support of its other operations.

Contingent Consideration Liabilities

The estimated fair values of these contingent consideration liabilities are measured on a recurring basis using a probability-weighted discounted cash flow method, which considers significant inputs not observable in the market and are Level 3 inputs.

Commitments and Contingencies

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.

The assessment of whether a loss is probable or reasonably possible, and whether the loss or a range of loss is estimable, often involves a series of complex judgments about future events. 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 and taking into account, among other things, negotiations with claimants, discovery, settlements and payments, judicial rulings, arbitration and mediation decisions, advice of internal and external legal counsel, and other information and events pertaining to a particular matter. Costs incurred for litigation are expensed as incurred. 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. However, management’s judgment may prove materially inaccurate, and such judgment is made subject to the known uncertainties of litigation.

Losses under these insurance programs are accrued based upon Quanta’s estimate of the ultimate liability for claims reported and an estimate of claims incurred but not reported, with assistance from third-party actuaries. These insurance liabilities are difficult to assess and estimate due to

unknown factors, including the severity of an injury, the extent of damage, the determination of Quanta’s liability in proportion to other parties, the number of incidents not reported and the overall claims environment. The accruals are based upon known facts and historical trends, and management believes such accruals are adequate.