Controlling Shareholder	12 Months Ended
Controlling Shareholder	Sep. 30, 2025
Risks and Uncertainties [Abstract]
Controlling Shareholder [Text Block]	3. CONTROLLING SHAREHOLDER Tontine Associates, L.L.C. (“Tontine Associates”), together with its affiliates (collectively, “Tontine”) is the Company's controlling stockholder, owning approximately 54 percent of the Company’s outstanding common stock based on a Form 4 and a Schedule 13D/A filed by Tontine with the SEC on September 17, 2025 and the Company's shares outstanding as of November 17, 2025. Accordingly, Tontine has the ability to exercise significant control over our affairs, including the election of directors and most actions requiring the approval of shareholders. While Tontine is subject to certain restrictions under federal securities laws on sales of its shares as an affiliate, the Company has filed a resale shelf registration statement to register for resale a majority of the shares of IES common stock owned by Tontine. As long as the resale shelf registration statement remains effective and the Company remains eligible to use it, Tontine has the ability to resell any or all of its registered shares from time to time in one or more offerings, as described in the resale shelf registration statement and in any prospectus supplement filed in connection with an offering pursuant to the resale shelf registration statement. Should Tontine, or its underlying individual owners, sell or otherwise dispose of all or a significant portion of its position in IES, a change in ownership of IES could occur. A change of control would trigger the change of control provisions in a number of our material agreements, including our credit agreement, bonding agreements with our sureties and our executive severance plan. Jeffrey L. Gendell was appointed Executive Chairman of the Company effective July 1, 2025 after serving as Chief Executive Officer of the Company from October 1, 2020 to June 30, 2025, and as the Company's Interim Chief Executive Officer from July 31, 2020 to September 30, 2020. Mr. Gendell has also served as a director and as Chairman of the Board of Directors since November 2016. He is the managing member and founder of Tontine, and the brother of David B. Gendell, who has served as a member of our Board of Directors since February 2012, and who previously served as Interim Director of Operations from November 2017 to January 2019, as Vice Chairman of the Board from November 2016 to November 2017 and as Chairman of the Board from January 2015 to November 2016. David B. Gendell was an employee of Tontine from 2004 until January 2018. The Company is a party to a sublease agreement with Tontine Associates, for corporate office space in Greenwich, Connecticut. In December 2022, the Company entered into an amendment of the sublease agreement, which was set to terminate on February 28, 2023, to extend the term of the agreement through August 31, 2024 and to increase the monthly payments from approximately $8 to approximately $9 effective March 1, 2023. On August 1, 2024, the Company entered into an amendment of the sublease agreement to extend the term of the agreement through September 30, 2025, effective September 1, 2024. On August 1, 2025, the Company entered into an amendment of the sublease agreement to extend the term of the agreement through September 30, 2026. Payments by the Company are at a rate consistent with that paid by Tontine Associates to its landlord. On December 6, 2018, the Company entered into a Board Observer Letter Agreement (the "Observer Agreement") with Tontine Associates, in order to assist Tontine in managing its investment in the Company. Subject to the terms and conditions set forth in the Observer Agreement, the Company granted Tontine the right, at any time that Tontine holds at least 20% of the outstanding common stock of the Company, to appoint a representative to serve as an observer to the Board (the “Board Observer”). The Board Observer, who must be reasonably acceptable to those members of the Board who are not affiliates of Tontine, shall have no voting rights or other decision making authority. Subject to the terms and conditions set forth in the Observer Agreement, so long as Tontine has the right to appoint a Board Observer, the Board Observer will have the right to attend and participate in meetings of the Board and the committees thereof, subject to confidentiality requirements, and to receive reimbursement for reasonable out-of-pocket expenses incurred in his or her capacity as a Board Observer and such rights to coverage under the Company’s directors’ and officers’ liability insurance policy as are available to the Company’s directors.

IES Holdings, Inc. 10-K