Business and Organization	12 Months Ended
Business and Organization	Dec. 31, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Business and Organization	Business and Organization Limbach Holdings, Inc. (the “Company,” “we” or “us”), a Delaware corporation headquartered in Pittsburgh, Pennsylvania, was formed on July 20, 2016 as a result of a business combination with Limbach Holdings LLC (“LHLLC”). The Company is an integrated building systems solutions firm whose expertise is in the design, modular prefabrication, installation, management and maintenance of heating, ventilation, air-conditioning (“HVAC”), mechanical, electrical, plumbing and controls systems. The Company provides comprehensive facility services consisting of mechanical construction, full HVAC service and maintenance, energy audits and retrofits, engineering and design build services, constructability evaluation, equipment and materials selection, offsite/prefabrication construction, and the complete range of sustainable building solutions. The Company's customers operate in diverse industries including, but not limited to, healthcare, life sciences, data centers, industrial and light manufacturing, entertainment, education and government. The Company operates primarily in the Northeast, Mid-Atlantic, Southeast, Midwest, and Southwestern regions of the United States. The Company operates in two segments, which were renamed as of January 1, 2021 to reflect the Company's two distinct approaches to its customer base and to better align with its owner direct strategy. The previously named Construction segment is now known as General Contractor Relationships (“GCR”); the previously named Service segment is now known as Owner Direct Relationships (“ODR”). The Company's operating segments are based on the relationship with its customers, (i) GCR, in which the Company generally manages new construction or renovation projects that involve primarily HVAC, plumbing, or electrical services awarded to the Company by general contractors or construction managers, and (ii) ODR, in which the Company provides maintenance or service primarily on HVAC, plumbing or electrical systems, building controls and specialty contracting projects direct to, or assigned by, building owners or property managers. This work is primarily performed under fixed price, modified fixed price, and time and material contracts over periods of typically less than two years. Impact of the COVID-19 Pandemic In March 2020, the World Health Organization declared the outbreak of the coronavirus disease 2019 (“COVID-19”) a global pandemic. The COVID-19 pandemic has caused significant disruption and volatility on a global scale resulting in, among other things, an economic slowdown, impacts to global supply chains, and the possibility of a continued economic recession. In response to the COVID-19 outbreak, national and local governments around the world instituted certain measures, including travel bans, restrictions on group events and gatherings, shutdowns of certain non-essential businesses, curfews, shelter-in-place orders, recommendations to practice social distancing and vaccine mandates. Certain governmental actions have abated over time, but remain applicable to Limbach's operations in various ways, often varying by state. In some instances, these orders continued to affect certain projects in our GCR and ODR segments during 2021. In limited instances, during fiscal 2020, projects chose to shutdown work irrespective of the existence or applicability of government action. In most markets, construction is considered an essential business and the Company continued to staff its projects and perform work during fiscal 2020 and into 2021, and most of the projects that were in progress at the time shutdowns commenced were restarted. The Company continues to actively manage its response to the COVID-19 pandemic in collaboration with relevant parties and, given that the situation surrounding COVID-19 remains fluid, a number of Company-wide measures undertaken in response to COVID-19 remain in effect to continue to promote the safety and health of its employees and customers. The Company continues to monitor the short and long term impacts of the pandemic. While our employees and customers have adapted to a new work environment and there continues to be scientific, societal and economic progress to address the effect of COVID-19, there remains significant uncertainty about the future impacts of the pandemic, including the potential effects on our operations. We remain cautiously optimistic about the markets in which we operate and the customers we serve; however, the continued spread of the virus may impact economic activity and could cause projects to be delayed or canceled, or we may experience access restrictions to our customers’ facilities and project sites. Supply chain disruptions, material shortages and escalating commodity prices as a result of COVID-19 are expected to continue into 2022. During the fourth quarter of 2021, the Company was impacted by supply chain issues delaying equipment delivery, which resulted in revenue being pushed to future periods. The impact of the COVID-19 pandemic on the Company’s vendors and the pricing and availability of materials or supplies utilized in the Company’s operations continues to evolve and may have an adverse impact on the Company’s operations in future periods. The ongoing effects of the pandemic, including decreased consumer confidence and economic instability, can make it extremely difficult for our customers, our vendors and us to accurately forecast and plan future business activities, and could cause constrained spending on our services, delays and a lengthening of our business development efforts, the demand for more favorable pricing or other terms, and/or difficulty in collection of our accounts receivable. Our clients may face budget deficits or other financial constraints that prohibit them from funding proposed and existing projects. During the fourth quarter of 2020 and for a portion of the year ended December 31, 2021, several of our business units experienced slowdowns in the closing of sales related to the ongoing effects of the pandemic, which impacted our revenue and profitability. These impacts may continue as the pandemic persists. Further, ongoing economic instability in the global markets, including from the pandemic, could limit our ability to access the capital markets at a time when we would like, or need, to raise capital, which could have an impact on our ability to react to changing business conditions or new opportunities. If economic conditions remain uncertain or weaken, or spending continues to be reduced, our financial condition and results of operations may be adversely affected.