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Employee Benefit Plans (Details) $ in Thousands | 12 Months Ended
--- | ---
Sep. 30, 2017 USD ($) years | Sep. 30, 2016 USD ($) | Sep. 30, 2015 USD ($)
Executive Saving Plan [Abstract] |  |  |
Maximum percentage of salary permitted for deferral | 75.00% |  |
Post Retirement Benefit Plan [Abstract] |  |  |
Defined Benefit Plan, Percentage Vest After Ten Years Of Service | 50.00% |  |
Denfied Benefits Plan, Annual Percentage Vested | 10.00% |  |
Defined Benefit Plan, Plans with Benefit Obligations in Excess of Plan Assets, Aggregate Benefit Obligation | $ 815 | $ 875 |
Expense Related to Post Retirement Benefit Plan | $ 0 | $ 65 | $ 11
Multiemployer Plans [Abstract] |  |  |
Percentage of Plan Funded |  | 82.82% |
IES 401(k) Plan [Member] |  |  |
Defined Contribution Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan Plans Fully Vested Number Of Years | years | 3 |  |
Defined Benefit Plan Minimum Age | years | 21 |  |
Minimum Employment Term For Eligibility | 60 days |  |
401(k) Matching Expense | $ 1,157 | $ 737 | $ 387

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- Definition Arrangment made with employees to defer a maximum percentage of their base salary and/or bonus for a Plan Year. + References No definition available. + Details
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- Definition Fixed annual payments made to employees under defined benefits plan, and as specified in the related agreements, after they have attained 62 years of age. + References No definition available. + Details
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- Definition Maximum percentage of benefits vest after ten years of employment service. + References No definition available. + Details
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- Definition The number of years in service after which the benefits are fully vested. + References No definition available. + Details
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- Definition Annual percentage increase in defined benefit vest. + References No definition available. + Details
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- Definition Funded percenatge of multiemployer pension plan for collective barganning employees. + References No definition available. + Details
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- References No definition available. + Details
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- References No definition available. + Details
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- Definition Amount of other defined benefit plan costs. + References No definition available. + Details
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- Definition If aggregate disclosures are presented, the aggregate benefit obligation for plans with benefit obligations in excess of plan assets as of the measurement date of each statement of financial position presented. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e2417-114920 + Details
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- Definition The amount of the cost recognized during the period for defined contribution plans. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 70 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=49170846&loc=d3e28014-114942 + Details
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