Arrangment made with employees to defer a maximum percentage of their base salary and/or bonus for a Plan Year.

No definition available.

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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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Namespace Prefix:	iesc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

No authoritative reference available.

+ References

No definition available.

+ Details

Name:	iesc_DefinedContributionPlanCostRecognizedIes
Namespace Prefix:	iesc_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Annual percentage increase in defined benefit vest.

+ References

No definition available.

+ Details

Name:	iesc_DenfiedBenefitsPlanAnnualPercentageVested
Namespace Prefix:	iesc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Details

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Data Type:	xbrli:stringItemType
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Period Type:	duration

- Definition

Funded percenatge of multiemployer pension plan for collective barganning employees.

+ References

No definition available.

+ Details

Name:	iesc_PercentageOfPlanFunded
Namespace Prefix:	iesc_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Details

Name:	iesc_PostRetirementBenefitPlanAbstract
Namespace Prefix:	iesc_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

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Namespace Prefix:	us-gaap_
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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=28361610&loc=d3e2417-114920

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Details

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Employee Benefit Plans (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Sep. 30, 2012	Sep. 30, 2014	Dec. 31, 2013	Sep. 30, 2013
401 (k) Plan [Abstrract]
Defined Contribution Plan Cost Recognized - IES	$ 0
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		$ 853		$ 828
MultiemployerPlansAbstract
Percentage of Plan Funded			85.30%