Commitments and Contingencies	6 Months Ended
Jun. 30, 2020
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Legal. The Company is continually engaged in administrative proceedings, arbitrations, and litigation with owners, general contractors, suppliers, and other unrelated parties, all arising in the ordinary courses of business. In the opinion of the Company’s management, the results of these actions will not have a material adverse effect on the financial position, results of operations, or cash flows of the Company. LFS and Harper, wholly-owned subsidiaries of the Company, were parties to a lawsuit involving a Harper employee who was alleged to be in the course and scope of his employment at the time the personal car he was operating collided with another car causing injuries to three persons and one fatality. On or about October 12, 2018, the plaintiffs agreed to settle and dismiss the lawsuit in exchange for an aggregate payment of $30.0 million from LFS and Harper, which amounts were paid entirely by the Company’s insurance carriers. The Company will not have any monetary exposure. The $30.0 million amounts due from the Company’s insurance carriers and due to the plaintiffs were included in the captions labeled as other current assets and accrued expenses and other current liabilities, respectively, in the consolidated balance sheet as of December 31, 2018 and were paid in February 2019. On November 13, 2019, claimant, Lanzo Trenchless Technologies, Inc. - North, filed a Demand for Arbitration in the state of Michigan against our wholly-owned subsidiary, Limbach Company LLC. The demand seeks damages in excess of $0.4 million based upon the allegation that Limbach breached a construction contract by improperly terminating Lanzo’s subcontract, and for withholding payment from Lanzo based upon deficient performance. Limbach has asserted a counterclaim seeking damages caused by Lanzo’s deficient performance. A binding arbitration proceeding is anticipated later in 2020. On January 23, 2020, plaintiff, Bernards Bros. Inc., filed a complaint against Limbach Holdings, Inc. in Superior Court of the State of California for the County of Los Angeles against Limbach Holdings, Inc. The complaint alleges that our Southern California operations refused to honor a proposal made to Bernards to act as a subcontractor on a construction project, and that, as a result of the wrongful failure to honor the proposal, Bernards suffered damages in excess of $3.0 million, including alleged increased costs for hiring a different subcontractor to perform the work. The Company intends to vigorously defend the suit. The schedule of these proceedings has been delayed due to COVID-19 related court-closings, such that a date for trial is currently uncertain. On April 17, 2020, plaintiff, LA Excavating, Inc., filed a complaint against our wholly-owned subsidiary, Limbach Company LP, and several other parties, in Superior Court of the State of California, for the County of Los Angeles. The complaint seeks damages of approximately $1.0 million for alleged failure to pay contract balances and extra work ordered by Limbach, as well as seeks to enforce payment obligations under payment and stop notice release bonds. The Company disputes the allegations and intends to vigorously defend the suit. The schedule of these proceedings has been delayed due to COVID-19 related court-closings, such that a date for trial is currently uncertain. Surety. The terms of our construction contracts frequently require that we obtain from surety companies, and provide to our customers, payment and performance bonds (“Surety Bonds”) as a condition to the award of such contracts. The Surety Bonds secure our payment and performance obligations under such contracts, and we have agreed to indemnify the surety companies for amounts, if any, paid by them in respect of Surety Bonds issued on our behalf. In addition, at the request of labor unions representing certain of our employees, Surety Bonds are sometimes provided to secure obligations for wages and benefits payable to or for such employees. Public sector contracts require Surety Bonds more frequently than private sector contracts, and accordingly, our bonding requirements typically increase as the amount of public sector work increases. As of June 30, 2020, the Company had approximately $128.6 million in surety bonds outstanding. The Surety Bonds are issued by surety companies in return for premiums, which vary depending on the size and type of bond. Collective Bargaining Agreements. Many of the Company’s craft labor employees are covered by collective bargaining agreements. The agreements require the Company to pay specified wages, provide certain benefits and contribute certain amounts to multi-employer pension plans. If the Company withdraws from any of the multi-employer pension plans or if the plans were to otherwise become underfunded, the Company could incur additional liabilities related to these plans. Although the Company has been informed that some of the multi-employer pension plans to which it contributes have been classified as “critical” status, the Company is not currently aware of any significant liabilities related to this issue.

Commitments and Contingencies

Legal. The Company is continually engaged in administrative proceedings, arbitrations, and litigation with owners, general contractors, suppliers, and other unrelated parties, all arising in the ordinary courses of business. In the opinion of the Company’s management, the results of these actions will not have a material adverse effect on the financial position, results of operations, or cash flows of the Company.

LFS and Harper, wholly-owned subsidiaries of the Company, were parties to a lawsuit involving a Harper employee who was alleged to be in the course and scope of his employment at the time the personal car he was operating collided with another car causing injuries to three persons and one fatality. On or about October 12, 2018, the plaintiffs agreed to settle and dismiss the lawsuit in exchange for an aggregate payment of $30.0 million from LFS and Harper, which amounts were paid entirely by the Company’s insurance carriers. The Company will not have any monetary exposure. The $30.0 million amounts due from the Company’s insurance carriers and due to the plaintiffs were included in the captions labeled as other current assets and accrued expenses and other current liabilities, respectively, in the consolidated balance sheet as of December 31, 2018 and were paid in February 2019.

On November 13, 2019, claimant, Lanzo Trenchless Technologies, Inc. - North, filed a Demand for Arbitration in the state of Michigan against our wholly-owned subsidiary, Limbach Company LLC. The demand seeks damages in excess of $0.4 million based upon the allegation that Limbach breached a construction contract by improperly terminating Lanzo’s subcontract, and for withholding payment from Lanzo based upon deficient performance. Limbach has asserted a counterclaim seeking damages caused by Lanzo’s deficient performance. A binding arbitration proceeding is anticipated later in 2020.

On January 23, 2020, plaintiff, Bernards Bros. Inc., filed a complaint against Limbach Holdings, Inc. in Superior Court of the State of California for the County of Los Angeles against Limbach Holdings, Inc. The complaint alleges that our Southern California operations refused to honor a proposal made to Bernards to act as a subcontractor on a construction project, and that, as a result of the wrongful failure to honor the proposal, Bernards suffered damages in excess of $3.0 million, including alleged increased costs for hiring a different subcontractor to perform the work. The Company intends to vigorously defend the suit. The schedule of these proceedings has been delayed due to COVID-19 related court-closings, such that a date for trial is currently uncertain.

On April 17, 2020, plaintiff, LA Excavating, Inc., filed a complaint against our wholly-owned subsidiary, Limbach Company LP, and several other parties, in Superior Court of the State of California, for the County of Los Angeles. The complaint seeks damages of approximately $1.0 million for alleged failure to pay contract balances and extra work ordered by Limbach, as well as seeks to enforce payment obligations under payment and stop notice release bonds. The Company disputes the allegations and intends to vigorously defend the suit. The schedule of these proceedings has been delayed due to COVID-19 related court-closings, such that a date for trial is currently uncertain.

Surety. The terms of our construction contracts frequently require that we obtain from surety companies, and provide to our customers, payment and performance bonds (“Surety Bonds”) as a condition to the award of such contracts. The Surety Bonds secure our payment and performance obligations under such contracts, and we have agreed to indemnify the surety companies for amounts, if any, paid by them in respect of Surety Bonds issued on our behalf. In addition, at the request of labor unions representing certain of our employees, Surety Bonds are sometimes provided to secure obligations for wages and benefits payable to or for such employees. Public sector contracts require Surety Bonds more frequently than private sector contracts, and accordingly, our bonding requirements typically increase as the amount of public sector work increases. As of June 30, 2020, the Company had approximately $128.6 million in surety bonds outstanding. The Surety Bonds are issued by surety companies in return for premiums, which vary depending on the size and type of bond.

Collective Bargaining Agreements. Many of the Company’s craft labor employees are covered by collective bargaining agreements. The agreements require the Company to pay specified wages, provide certain benefits and contribute certain amounts to multi-employer pension plans. If the Company withdraws from any of the multi-employer pension plans or if the plans were to otherwise become underfunded, the Company could incur additional liabilities related to these plans. Although the Company has been informed that some of the multi-employer pension plans to which it contributes have been classified as “critical” status, the Company is not currently aware of any significant liabilities related to this issue.