Commitments and Contingencies	12 Months Ended
Dec. 31, 2023
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	12. COMMITMENTS AND CONTINGENCIES Commercial commitments Performance and bid bonds are customarily required for dredging and marine construction projects. The Company has bonding agreements with Argonaut Insurance Company, ACE Holdings, Liberty Mutual Insurance Company and Philadelphia Indemnity Insurance Company, (collectively, the “Sureties”) under which the Company can obtain performance, bid and payment bonds. The Company also currently has outstanding bonds with Travelers Casualty and Surety Company of America, Berkley Insurance Company and Zurich American Insurance Company. Bid bonds are generally obtained for a percentage of bid value and amounts outstanding typically range from $1,000 to $10,000. At December 31, 2023, the Company had outstanding performance bonds with a notional amount of approximately $960,906. The revenue value remaining in backlog related to the projects totaled approximately $546,759. Certain foreign projects performed by the Company have warranty periods, typically spanning no more than one to three years beyond project completion, whereby the Company retains responsibility to maintain the project site to certain specifications during the warranty period. Generally, any potential liability of the Company is mitigated by insurance, shared responsibilities with consortium partners, and/or recourse to owner-provided specifications. Legal proceedings and other contingencies As is customary with negotiated contracts and modifications or claims to competitively bid contracts with the federal government, the government has the right to audit the books and records of the Company to ensure compliance with such contracts, modifications, or claims, and the applicable federal laws. The government has the ability to seek a price adjustment based on the results of such audit. Any such audits have not had, and are not expected to have, a material impact on the financial position, operations, or cash flows of the Company. Various legal actions, claims, assessments and other contingencies arising in the ordinary course of business are pending against the Company and certain of its subsidiaries. The Company will defend itself vigorously on all matters. These matters are subject to many uncertainties, and it is possible that some of these matters could ultimately be decided, resolved, or settled adversely to the Company. Although the Company is subject to various claims and legal actions that arise in the ordinary course of business, except as described below, the Company is not currently a party to any material legal proceedings or environmental claims. The Company records an accrual when it is probable a liability has been incurred and the amount of loss can be reasonably estimated. The Company does not believe any of these proceedings, individually or in the aggregate, would be expected to have a material effect on results of operations, cash flows or financial condition. On April 23, 2014, the Company completed the sale of NASDI, LLC (“NASDI”) and Yankee Environmental Services, LLC (“Yankee”), which together comprised the Company’s historical demolition business, to a privately-owned demolition company. The Company has been involved in litigation relating to this sale, and on April 11, 2022 the Supreme Court of Delaware affirmed an earlier decision by Delaware Court of Chancery granting the Company a $21,934 judgment relating to the buyer's default of its obligations to indemnify the Company for losses resulting from failure to perform in accordance with terms of a surety performance bond. Following this judgment, the Company continued to aggressively pursue collection from the buyer on outstanding amounts owed under the sale and the indemnification. On April 24, 2023, the Company settled the remaining litigation related to the sale and subsequent buyer's default of its obligations to indemnify the Company. The settlement called for a one-time payment to the Company from entities affiliated with the buyer in the amount of $1,250, a disbursement to the Company from a litigation escrow account in the amount of $680 and a release of funds retained by New York City to the Company in connection with a pre-purchase construction project, which is expected to be approximately $800 after the payment of related expenses. For the year ended December 31, 2023, the Company recorded a $2,410 benefit in cost of contract revenues and $784 in other income related to the settlement and the release of certain liabilities related to the original sale. As of December 31, 2023, the Company has received $1,930 of the settlement, with the remaining $800 yet to be released by New York City. This amount is recorded in prepaid expenses and other current assets in the consolidated balance sheets. Lease obligations The Company leases certain operating equipment and office facilities under long-term operating leases expiring at various dates through 2030. The equipment leases contain renewal or purchase options that specify prices at the then fair value upon the expiration of the lease terms. The leases also contain default provisions that are triggered by an acceleration of debt maturity under the terms of the Company’s Amended Credit Agreement, or, in certain instances, cross default to other equipment leases and certain lease arrangements require that the Company maintain certain financial ratios comparable to those required by its Amended Credit Agreement. Additionally, the leases typically contain provisions whereby the Company indemnifies the lessors for the tax treatment attributable to such leases based on the tax rules in place at lease inception. The tax indemnifications do not have a contractual dollar limit. To date, no lessors have asserted any claims against the Company under these tax indemnification provisions.

Commitments and Contingencies

12 Months Ended

Dec. 31, 2023

Commitments and Contingencies Disclosure [Abstract]

12. COMMITMENTS AND CONTINGENCIES

Commercial commitments

Performance and bid bonds are customarily required for dredging and marine construction projects. The Company has bonding agreements with Argonaut Insurance Company, ACE Holdings, Liberty Mutual Insurance Company and Philadelphia Indemnity Insurance Company, (collectively, the “Sureties”) under which the Company can obtain performance, bid and payment bonds. The Company also currently has outstanding bonds with Travelers Casualty and Surety Company of America, Berkley Insurance Company and Zurich American Insurance Company. Bid bonds are generally obtained for a percentage of bid value and amounts outstanding typically range from $1,000 to $10,000. At December 31, 2023, the Company had outstanding performance bonds with a notional amount of approximately $960,906. The revenue value remaining in backlog related to the projects totaled approximately $546,759.

Certain foreign projects performed by the Company have warranty periods, typically spanning no more than one to three years beyond project completion, whereby the Company retains responsibility to maintain the project site to certain specifications during the warranty period. Generally, any potential liability of the Company is mitigated by insurance, shared responsibilities with consortium partners, and/or recourse to owner-provided specifications.

Legal proceedings and other contingencies

As is customary with negotiated contracts and modifications or claims to competitively bid contracts with the federal government, the government has the right to audit the books and records of the Company to ensure compliance with such contracts, modifications, or claims, and the applicable federal laws. The government has the ability to seek a price adjustment based on the results of such audit. Any such audits have not had, and are not expected to have, a material impact on the financial position, operations, or cash flows of the Company.

Various legal actions, claims, assessments and other contingencies arising in the ordinary course of business are pending against the Company and certain of its subsidiaries. The Company will defend itself vigorously on all matters. These matters are subject to many uncertainties, and it is possible that some of these matters could ultimately be decided, resolved, or settled adversely to the Company. Although the Company is subject to various claims and legal actions that arise in the ordinary course of business, except as described below, the Company is not currently a party to any material legal proceedings or environmental claims. The Company records an accrual when it is probable a liability has been incurred and the amount of loss can be reasonably estimated. The Company does not believe any of these proceedings, individually or in the aggregate, would be expected to have a material effect on results of operations, cash flows or financial condition.

On April 23, 2014, the Company completed the sale of NASDI, LLC (“NASDI”) and Yankee Environmental Services, LLC (“Yankee”), which together comprised the Company’s historical demolition business, to a privately-owned demolition company. The Company has been involved in litigation relating to this sale, and on April 11, 2022 the Supreme Court of Delaware affirmed an earlier decision by Delaware Court of Chancery granting the Company a $21,934 judgment relating to the buyer's default of its obligations to indemnify the Company for losses resulting from failure to perform in accordance with terms of a surety performance bond. Following this judgment, the Company continued to aggressively pursue collection from the buyer on outstanding amounts owed under the sale and the indemnification. On April 24, 2023, the Company settled the remaining litigation related to the sale and subsequent buyer's default of its obligations to indemnify the Company. The settlement called for a one-time payment to the Company from entities affiliated with the buyer in the amount of $1,250, a disbursement to the Company from a litigation escrow account in the amount of $680 and a release of funds retained by New York City to the Company in connection with a pre-purchase construction project, which is expected to be approximately $800 after the payment of related expenses. For the year ended December 31, 2023, the Company recorded a $2,410 benefit in cost of contract revenues and $784 in other income related to the settlement and the release of certain liabilities related to the original sale. As of December 31, 2023, the Company has received $1,930 of the settlement, with the remaining $800 yet to be released by New York City. This amount is recorded in prepaid expenses and other current assets in the consolidated balance sheets.

Lease obligations

The Company leases certain operating equipment and office facilities under long-term operating leases expiring at various dates through 2030. The equipment leases contain renewal or purchase options that specify prices at the then fair value upon the expiration of the lease terms. The leases also contain default provisions that are triggered by an acceleration of debt maturity under the terms of the Company’s Amended Credit Agreement, or, in certain instances, cross default to other equipment leases and certain lease arrangements require that the Company maintain certain financial ratios comparable to those required by its Amended Credit Agreement. Additionally, the leases typically contain provisions whereby the Company indemnifies the lessors for the tax treatment attributable to such leases based on the tax rules in place at lease inception. The tax indemnifications do not have a contractual dollar limit. To date, no lessors have asserted any claims against the Company under these tax indemnification provisions.