Employee Benefit Plans	3 Months Ended
Dec. 31, 2021
Retirement Benefits [Abstract]
Compensation and Employee Benefit Plans [Text Block]	8. EMPLOYEE BENEFIT PLANS 401(k) Plan In November 1998, we established the IES Holdings, Inc. 401(k) Retirement Savings Plan. All full-time IES employees are eligible to participate on the first day of the month subsequent to completing sixty days of service and attaining age twenty one. Participants become vested in our matching contributions following three years of service. We also maintain several subsidiary retirement savings plans. During the three months ended December 31, 2021 and 2020, we recognized $921 and $706, respectively, in matching expense.

The entire disclosure for an entity's employee compensation and benefit plans, including, but not limited to, postemployment and postretirement benefit plans, defined benefit pension plans, defined contribution plans, non-qualified and supplemental benefit plans, deferred compensation, share-based compensation, life insurance, severance, health care, unemployment and other benefit plans.

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-Name Accounting Standards Codification
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-Name Accounting Standards Codification
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-Publisher FASB
-Name Accounting Standards Codification
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