With respect to a business combination completed during the period, this element provides a description of the business, other than the name, which may include the industry, size, products and other important information.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=65885119&loc=d3e1392-128463

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- Definition

Name of the acquired entity.

+ References

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- Definition

Description of the conditions for borrowing under the credit facility including the nature of any restrictions.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Describes the event or transaction that occurred between the balance sheet date and the date the financial statements are issued or available to be issued.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6842918&loc=SL6314017-165662

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- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

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Subsequent Events (Details)			1 Months Ended	9 Months Ended
Subsequent Events (Details)	Aug. 02, 2017	Jul. 14, 2017	Jul. 31, 2017	Jun. 30, 2017
Revolving Credit Facility [Member]
Subsequent Event [Line Items]
Credit Facility Covenant Terms				new covenant that requires the Company to maintain a minimum EBITDA (as defined in the Amended Credit Agreement) that will be tested quarterly on a trailing twelve month basis; increasing the minimum liquidity requirement applicable to the Company from 12.5% to 30% of the maximum revolver amount; raising the Company’s required fixed charge coverage ratio (the “FCCR”) to 1.1:1.0 from 1.0:1.0; and requiring that the FCCR be tested quarterly regardless of the Company’s liquidity levels.
Subsequent Event [Member]
Subsequent Event [Line Items]
Subsequent Event Description			we made the decision to wind-down operations at two branches of our Commercial & Industrial segment.
Subsequent Event [Member] \| NEXT Business Acquisition [Member]
Subsequent Event [Line Items]
Subsequent Event Description		On July 14, 2017, the Company acquired 80% of the membership interests of NEXT Electric, LLC (“NEXT”)
Name of Acquired Business		NEXT Electric, LLC (“NEXT”)
Description of Acquired Business		a Milwaukee, Wisconsin-based electrical contractor specializing in the design, installation and maintenance of electrical systems for commercial, industrial, healthcare, water treatment and education end markets.
Subsequent Event [Member] \| Revolving Credit Facility [Member]
Subsequent Event [Line Items]
Subsequent Event Description		we entered into an amendment and joinder to our Amended Credit Agreement permitting certain transactions related to our acquisition of NEXT
Credit Facility Covenant Terms	we entered into an amendment to our Amended Credit Agreement, which modifies the definition of EBITDA used in calculating our financial covenants to exclude the results from the Denver and Roanoke branches, up to a maximum exclusion of $5 million for a given measurement period. The amendment also reduces the minimum EBITDA requirement for the quarters ended December 31, 2017 and March 31, 2018 from $32,500 to $30,000 and $35,000 to $32,500, respectively. Minimum EBITDA requirements for all other quarters are unchanged.