Basis of Presentation	6 Months Ended
Jun. 30, 2023
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Basis of Presentation	1. Basis of presentation The unaudited condensed consolidated financial statements and notes herein should be read in conjunction with the audited consolidated financial statements of Great Lakes Dredge & Dock Corporation and Subsidiaries (the “Company” or “Great Lakes”) and the notes thereto, included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2022. The condensed consolidated financial statements included herein have been prepared by the Company without audit, pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”). Certain information and footnote disclosures normally included in financial statements prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”) have been condensed or omitted pursuant to the SEC’s rules and regulations, although management believes that the disclosures are adequate and make the information presented not misleading. In the opinion of management, all adjustments, which are of a normal and recurring nature (except as otherwise noted), that are necessary to present fairly the Company’s financial position as of June 30, 2023 and December 31, 2022, and its results of operations for the three and six months ended June 30, 2023 and 2022 and cash flows for the six months ended June 30, 2023 and 2022 have been included. The components of costs of contract revenues include labor, equipment (including depreciation, maintenance, insurance and long-term rentals), subcontracts, fuel, supplies, short-term rentals and project overhead. Hourly labor is generally hired on a project-by-project basis. Costs of contract revenues vary significantly depending on the type and location of work performed and assets utilized. The Company has one operating segment which is also the Company’s reportable segment and reporting unit of which the Company tests goodwill for impairment. The Company performed its most recent test of impairment as of October 1, 2022 with no indication of impairment as of the test date. As of the test date, the fair value of the reporting unit was in excess of its carrying value by at least 10%. When performing the quantitative test, the Company assessed the fair values of its reporting unit using both a market-based approach and an income-based approach. The assessment used estimates based on assumptions that the Company believes to be reasonable, but such assumptions are subject to unpredictability and uncertainty. Likewise, changes in terminal value and discount rate assumptions, unfavorable economic environment or market conditions and other factors in the future may cause a different assessment. Changes in these estimates and assumptions could materially affect the determination of fair value and may result in the impairment of goodwill in the event that actual results differ from those estimates. The Company will continue to monitor for changes in facts or circumstances that may impact its estimates. The Company will perform its next scheduled annual test of goodwill in the third quarter of 2023. The condensed consolidated results of operations and comprehensive income (loss) for the interim periods presented herein are not necessarily indicative of the results to be expected for the full year.

Basis of Presentation

6 Months Ended

Jun. 30, 2023

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Basis of presentation

The unaudited condensed consolidated financial statements and notes herein should be read in conjunction with the audited consolidated financial statements of Great Lakes Dredge & Dock Corporation and Subsidiaries (the “Company” or “Great Lakes”) and the notes thereto, included in the Company’s Annual Report on Form 10-K for the year ended December 31, 2022. The condensed consolidated financial statements included herein have been prepared by the Company without audit, pursuant to the rules and regulations of the Securities and Exchange Commission (“SEC”). Certain information and footnote disclosures normally included in financial statements prepared in accordance with accounting principles generally accepted in the United States of America (“GAAP”) have been condensed or omitted pursuant to the SEC’s rules and regulations, although management believes that the disclosures are adequate and make the information presented not misleading. In the opinion of management, all adjustments, which are of a normal and recurring nature (except as otherwise noted), that are necessary to present fairly the Company’s financial position as of June 30, 2023 and December 31, 2022, and its results of operations for the three and six months ended June 30, 2023 and 2022 and cash flows for the six months ended June 30, 2023 and 2022 have been included.

The components of costs of contract revenues include labor, equipment (including depreciation, maintenance, insurance and long-term rentals), subcontracts, fuel, supplies, short-term rentals and project overhead. Hourly labor is generally hired on a project-by-project basis. Costs of contract revenues vary significantly depending on the type and location of work performed and assets utilized.

The Company has one operating segment which is also the Company’s reportable segment and reporting unit of which the Company tests goodwill for impairment. The Company performed its most recent test of impairment as of October 1, 2022 with no indication of impairment as of the test date. As of the test date, the fair value of the reporting unit was in excess of its carrying value by at least 10%. When performing the quantitative test, the Company assessed the fair values of its reporting unit using both a market-based approach and an income-based approach. The assessment used estimates based on assumptions that the Company believes to be reasonable, but such assumptions are subject to unpredictability and uncertainty. Likewise, changes in terminal value and discount rate assumptions, unfavorable economic environment or market conditions and other factors in the future may cause a different assessment. Changes in these estimates and assumptions could materially affect the determination of fair value and may result in the impairment of goodwill in the event that actual results differ from those estimates. The Company will continue to monitor for changes in facts or circumstances that may impact its estimates. The Company will perform its next scheduled annual test of goodwill in the third quarter of 2023.

The condensed consolidated results of operations and comprehensive income (loss) for the interim periods presented herein are not necessarily indicative of the results to be expected for the full year.