Business and Organization	9 Months Ended
Business and Organization	Sep. 30, 2021
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Business and Organization	Note 1: Business and Organization Organization Custom Truck One Source, Inc., formerly Nesco Holdings, Inc., a Delaware corporation, and its wholly owned subsidiaries are engaged in the business of providing a range of services and products to customers through rentals and sales of specialty equipment, rentals and sales of aftermarket parts and services related to the specialty equipment, and repair, maintenance and customization services related to that equipment. Immediately following the acquisition by Nesco Holdings II, Inc. of Custom Truck One Source, L.P. (“Custom Truck LP”) as discussed in Note 3: Business Combination, on April 1, 2021 (the “Acquisition”), Nesco Holdings, Inc. (“Nesco Holdings”) changed its name to “Custom Truck One Source, Inc.” and changed The New York Stock Exchange ticker for its shares of common stock (“Common Stock”) from “NSCO” to “CTOS,” and the ticker of its redeemable warrants from “NSCO.WS” to “CTOS.WS.” Terms such as, “we,” “our,” “us,” or “the Company” refer to Nesco Holdings prior to the Acquisition, and to the combined company after the Acquisition. Unless the context otherwise requires, the term “Nesco” or “Nesco Holdings” as used in these financial statements means Nesco Holdings and its consolidated subsidiaries prior to the Acquisition, and the term “Custom Truck LP” means Custom Truck LP and its consolidated subsidiaries prior to and on the date of the Acquisition. We are a specialty equipment provider to the electric utility transmission and distribution, telecommunications, rail and other infrastructure-related industries in North America. Our core business relates to our new equipment inventory and rental fleet of specialty equipment that is utilized by service providers in infrastructure development and improvement work. We offer our specialized equipment to a diverse customer base, including utilities and contractors, for the maintenance, repair, upgrade, and installation of critical infrastructure assets, including distribution and transmission electric lines, telecommunications networks and rail systems, as well as for lighting and signage. We rent, produce, sell and service a broad range of new and used equipment, including bucket trucks, digger derricks, dump trucks, cranes, service trucks, and heavy-haul trailers. Following the Acquisition, we changed our reportable segments to be consistent with how we currently manage the business, representing three reporting segments: Equipment Rental Solutions (“ERS”), Truck and Equipment Sales (“TES”) and Aftermarket Parts and Services (“APS”). Segment information provided within this Quarterly Report on Form 10-Q, including Note 19: Segments, has been adjusted for all prior periods to be consistent with the current reportable segment presentation. Equipment Rental Solutions (“ERS”) Segment We own a broad range of new and used specialty equipment, including truck-mounted aerial lifts, cranes, service trucks, dump trucks, trailers, digger derricks and other machinery and equipment. The majority of our rental fleet can be used across a variety of end-markets, which coincides with the needs of many of our customers who operate in multiple end-markets. As is customary for equipment rental companies, we sell used equipment out of our rental fleet to end user customers. These sales are often made in response to specific customer requests. These sales offer customers an opportunity to buy well-maintained equipment with long remaining useful lives and enable us to effectively manage the age and mix of our rental fleet to match current market demand. We also employ rental purchase options on a select basis, which provide a buyout option with an established purchase price that decreases over time as rental revenue is collected. Customers are given credit against such purchase price for a portion of the amounts paid over the life of the rental, allowing customers the flexibility of a rental with the option to purchase at any time at a known price. Activities in our ERS segment consist of the rental and sale from the rental fleet, of the foregoing products. Truck and Equipment Sales (“TES”) Segment We offer a broad variety of new equipment for sale to be used across our end-markets, which can be modified to meet our customers’ specific needs. We believe that our integrated production capabilities and extensive knowledge gained over a long history of selling equipment have established us as a trusted partner for customers seeking tailored solutions with short lead times. In support of these activities, we primarily employ a direct-to-customer sales model, leveraging our dedicated salesforce of industry and product managers, who are focused on driving national and local sales. We also opportunistically engage in the sale of used equipment purchased from third parties or received via trade-ins from new equipment sales customers. In all of these cases, we will sell used equipment directly to customers, rather than relying on auctions. Activities in our TES segment consist of the production and sale of new and used specialty equipment and vocational trucks, which includes equipment from leading original equipment manufacturers (“OEMs”) across our end-markets, as well as our Load King© brand. Aftermarket Parts and Services (“APS”) Segment The APS segment includes the sale of specialized aftermarket parts, including captive parts related to our Load King© brand, used in the maintenance and repair of the equipment we sell and rent. Specialized tools, including stringing blocks, insulated hot stick, and rigging equipment, are sold or rented to customers on an individual basis or in packaged specialty kits. We also provide truck and equipment maintenance and repair services, which is executed throughout our nationwide branch network and fleet of mobile technicians supported by our 24/7 call center based in Kansas City, Missouri.