Operating Segments (Details) - USD ($) $ in Thousands	3 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Sep. 30, 2017
Segment Reporting Information [Line Items]
Revenues	$ 198,300	$ 192,178
Cost of Services	165,236	156,996
Gross Profit	33,064	35,182
Selling, General and Administrative Expense	30,089	28,194
Loss (gain) on sale of assets	(14)	(7)
Income (loss) from operations	2,989	6,995
Depreciation and amortization	2,208	2,059
Capital Expenditures	1,203	1,796
Assets	380,666	391,992	$ 424,494
Commercial & Industrial [Member]
Segment Reporting Information [Line Items]
Revenues	53,002	53,956
Cost of Services	48,159	47,850
Gross Profit	4,843	6,106
Selling, General and Administrative Expense	5,795	4,324
Loss (gain) on sale of assets	(12)	1
Income (loss) from operations	(940)	1,781
Depreciation and amortization	557	174
Capital Expenditures	510	1,079
Assets	63,085	53,922
Communications [Member]
Segment Reporting Information [Line Items]
Revenues	54,459	53,303
Cost of Services	45,339	45,332
Gross Profit	9,120	7,971
Selling, General and Administrative Expense	6,084	5,714
Loss (gain) on sale of assets	(1)	0
Income (loss) from operations	3,037	2,257
Depreciation and amortization	216	174
Capital Expenditures	75	1,079
Assets	66,522	69,884
Infrastructure Solutions [Member]
Segment Reporting Information [Line Items]
Revenues	21,685	18,477
Cost of Services	17,000	13,102
Gross Profit	4,685	5,375
Selling, General and Administrative Expense	4,557	4,100
Loss (gain) on sale of assets	(1)	(8)
Income (loss) from operations	129	1,283
Depreciation and amortization	1,243	1,323
Capital Expenditures	140	81
Assets	101,026	89,110
Residential [Member]
Segment Reporting Information [Line Items]
Revenues	69,154	66,442
Cost of Services	54,738	50,712
Gross Profit	14,416	15,730
Selling, General and Administrative Expense	10,366	10,553
Loss (gain) on sale of assets	0	0
Income (loss) from operations	4,050	5,177
Depreciation and amortization	141	150
Capital Expenditures	478	239
Assets	50,342	49,307
Corporate [Member]
Segment Reporting Information [Line Items]
Revenues	0	0
Cost of Services	0	0
Gross Profit	0	0
Selling, General and Administrative Expense	3,287	3,503
Loss (gain) on sale of assets	0	0
Income (loss) from operations	(3,287)	(3,503)
Depreciation and amortization	51	64
Capital Expenditures	0	188
Assets	$ 99,691	$ 129,769

Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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The aggregate total costs related to selling a firm's product and services, as well as all other general and administrative expenses. Direct selling expenses (for example, credit, warranty, and advertising) are expenses that can be directly linked to the sale of specific products. Indirect selling expenses are expenses that cannot be directly linked to the sale of specific products, for example telephone expenses, Internet, and postal charges. General and administrative expenses include salaries of non-sales personnel, rent, utilities, communication, etc.

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