Revenue Recognition The Company adopted the requirements of Accounting Standards Update (ASU) 2014-09, Revenue from Contracts with Customers, which is also referred to as Accounting Standards Codification (ASC) Topic 606, under the modified retrospective transition approach effective January 1, 2019, with application to all existing contracts that were not substantially completed as of January 1, 2019. The Company adopted this standard for interim periods beginning after December 31, 2019, and recorded adjustments to the previously issued quarterly financial statements for the six months ended June 30, 2019. The impacts of adoption on the Companys retained earnings on January 1, 2019 was primarily related to variable consideration on unapproved change orders. The cumulative impact of adopting Topic 606 required net adjustments of $750,000 to the statement of operations between revenue, cost of revenue and income taxes, thereby reducing income for the six months ended June 30, 2019 and reducing the December 31, 2019 accumulated deficit. The Company also adjusted the cashflow statement as of June 30, 2019, to reflect adoption. Under Topic 606, revenue is recognized when control of promised goods and services is transferred to customers, and the amount of revenue recognized reflects the consideration to which an entity expects to be entitled in exchange for the goods and services transferred. Revenue is recognized by the Company primarily over time utilizing the cost-to-cost measure of progress for fixed price contracts and are based on cost for time and materials and other service contracts, consistent with the Companys previous revenue recognition practices. Contracts The Company derives revenue primarily from construction projects performed under contracts for specific projects requiring the construction and installation of an entire infrastructure system or specified units within an infrastructure system. The contracts contain multiple pricing options, including fixed price, time and materials, or unit price. Renewable energy projects are performed for private customers while our Specialty Civil projects are performed for a mix of various governmental entities. Revenue derived from projects billed on a fixed-price basis totaled 98.0% and 90.7% of consolidated revenue from operations for the three months ended June 30, 2020 and 2019, respectively, and totaled 97.2% and 90.5% for the six months ended June 30, 2020 and 2019, respectively. Revenue and related costs for construction contracts billed on a time and materials basis are recognized as the services are rendered. Revenue derived from projects billed on a time and materials basis totaled 2.0% and 9.3% of consolidated revenue from operations for the three months ended June 30, 2020 and 2019, respectively, and totaled 2.8% and 9.5% for the six months ended June 30, 2020 and 2019, respectively. Revenue from construction contracts is recognized over time using the cost-to-cost measure of progress for fixed price construction contracts. For these contracts, the cost-to-cost measure of progress best depicts the continuous transfer of control of goods or services to the customer. The contractual terms provide that the customer compensates the Company for services rendered. Contract costs include all direct materials, labor and subcontracted costs, as well as indirect costs related to contract performance, such as indirect labor, supplies, tools, repairs and the costs of capital equipment. The cost estimation and review process for recognizing revenue over time under the cost-to-cost method is based on the professional knowledge and experience of the Companys project managers, engineers and financial professionals. Management reviews estimates of total contract transaction price and total project costs on an ongoing basis. Changes in job performance, job conditions and managements assessment of expected variable consideration are factors that influence estimates of the total contract transaction price, total costs to complete those contracts and profit recognition. Changes in these factors could result in revisions to revenue and costs of revenue in the period in which the revisions are determined on a prospective basis, which could materially affect the Companys condensed consolidated results of operations for that period. Provisions for losses on uncompleted contracts are recorded in the period in which such losses are determined. Performance Obligations A performance obligation is a promise in a contract to transfer a distinct good or service to the customer and is the unit of account under Topic 606. The transaction price of a contract is allocated to a distinct performance obligation and recognized as revenue when or as the performance obligation is satisfied. The Companys contracts often require significant integrated services and, even when delivering multiple distinct services, are generally accounted for as a single performance obligation. Contract amendments and change orders are generally not distinct from the existing contract due to the significant integrated service provided in the context of the contract and are accounted for as a modification of the existing contract and performance obligation. With the exception of certain Specialty Civil service contracts, the majority of the Companys performance obligations are completed within one year. When more than one contract is entered into with a customer on or close to the same date, the Company evaluates whether those contracts should be combined and accounted for as a single contract as well as whether those contracts should be accounted for as more than one performance obligation. This evaluation requires significant judgment and is based on the facts and circumstances of the various contracts, which could change the amount of revenue and profit recognition in a given period depending upon the outcome of the evaluation. Remaining performance obligations represent the amount of unearned transaction prices for contracts, including approved and unapproved change orders. As of June 30, 2020, the amount of the Companys remaining performance obligations was $1.1 billion. The Company expects to recognize approximately 72.3% of its remaining performance obligations as revenue during 2020. Revenue recognized from performance obligations satisfied in previous periods was $(1.6) million and $1.0 million for the three months ended June 30, 2020 and 2019, respectively, and $(3.6) million and $3.8 million for the six months ended June 30, 2020 and 2019, respectively. Variable Consideration Transaction pricing for the Companys contracts may include variable consideration, such as unapproved change orders, claims, incentives and liquidated damages. Management estimates variable consideration for a performance obligation utilizing estimation methods that best predict the amount of consideration to which the Company will be entitled. Variable consideration is included in the estimated transaction price to the extent it is probable that a significant reversal of cumulative revenue recognized will not occur when the uncertainty associated with the variable consideration is resolved. Managements estimates of variable consideration and determination of whether to include estimated amounts in transaction price are based on legal opinions, past practices with the customer, specific discussions, correspondence or preliminary negotiations with the customer and all other relevant information that is reasonably available. The effect of a change in variable consideration on the transaction price of a performance obligation is typically recognized as an adjustment to revenue on a cumulative catch-up basis. To the extent unapproved change orders, claims and liquidated damages reflected in transaction price are not resolved in the Companys favor, or to the extent incentives reflected in transaction price are not earned, there could be reductions in, or reversals of, previously recognized revenue. As of June 30, 2020 and year ended December 31, 2019, the Company included approximately $63.5 million and $73.3 million, respectively, of unapproved change orders and/or claims in the transaction price for certain contracts that were in the process of being resolved in the normal course of business, including through negotiation, arbitration and other proceedings. These transaction price adjustments are included within Contract Assets or Contract Liabilities as appropriate. The Company actively engages with its customers to complete the final change order approval process, and generally expects these processes to be completed within one year. Amounts ultimately realized upon final acceptance by customers could be higher or lower than such estimated amounts. Disaggregation of Revenue The following tables disaggregate revenue by customers and services performed, which the Company believes best depicts how the nature, amount, timing and uncertainty of its revenue: (in thousands) Three Months Ended Six Months Ended June 30, 2020 June 30, 2019 June 30, 2020 June 30, 2019 Renewables Segment Wind $ 317,151 $ 179,069 565,688 $ 251,103 Solar 7,111 80 7,320 2,077 $ 324,262 $ 179,149 $ 573,008 $ 253,180 Specialty Civil Segment Heavy civil $ 103,721 $ 86,170 144,943 $ 136,285 Rail 32,321 37,780 79,378 80,389 Environmental 20,300 24,862 41,438 47,888 $ 156,342 $ 148,812 $ 265,759 $ 264,562