Operating Segments (Details) - USD ($) $ in Thousands	3 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Sep. 30, 2016
Segment Reporting Information [Line Items]
Revenues	$ 192,178	$ 150,766
Cost of Services	156,996	123,133
Gross Profit	35,182	27,633
Selling, General and Administrative Expense	28,194	22,511
Loss (gain) on sale of assets	(7)	1
Operating Income	6,995	5,121
Depreciation and amortization	2,059	816
Capital Expenditures	1,796	352
Assets	391,992	223,078	$ 394,340
Communications [Member]
Segment Reporting Information [Line Items]
Revenues	53,303	40,759
Cost of Services	45,332	32,602
Gross Profit	7,971	8,157
Selling, General and Administrative Expense	5,714	4,713
Loss (gain) on sale of assets	0	0
Operating Income	2,257	3,444
Depreciation and amortization	174	122
Capital Expenditures	1,079	85
Assets	69,884	38,896
Residential [Member]
Segment Reporting Information [Line Items]
Revenues	66,442	52,127
Cost of Services	50,712	40,455
Gross Profit	15,730	11,672
Selling, General and Administrative Expense	10,553	8,714
Loss (gain) on sale of assets	0	0
Operating Income	5,177	2,958
Depreciation and amortization	150	121
Capital Expenditures	239	42
Assets	49,307	37,326
Commercial & Industrial [Member]
Segment Reporting Information [Line Items]
Revenues	53,956	45,265
Cost of Services	47,850	40,407
Gross Profit	6,106	4,858
Selling, General and Administrative Expense	4,324	3,638
Loss (gain) on sale of assets	1	0
Operating Income	1,781	1,220
Depreciation and amortization	348	183
Capital Expenditures	209	148
Assets	53,922	45,630
Infrastructure Solutions [Member]
Segment Reporting Information [Line Items]
Revenues	18,477	12,615
Cost of Services	13,102	9,669
Gross Profit	5,375	2,946
Selling, General and Administrative Expense	4,100	2,700
Loss (gain) on sale of assets	(8)	1
Operating Income	1,283	245
Depreciation and amortization	1,323	322
Capital Expenditures	81	77
Assets	89,110	34,747
Corporate [Member]
Segment Reporting Information [Line Items]
Revenues	0	0
Cost of Services	0	0
Gross Profit	0	0
Selling, General and Administrative Expense	3,503	2,746
Loss (gain) on sale of assets	0	0
Operating Income	(3,503)	(2,746)
Depreciation and amortization	64	68
Capital Expenditures	188	0
Assets	$ 129,769	$ 66,479

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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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The cash outflow for purchases of and capital improvements on property, plant and equipment (capital expenditures), software, and other intangible assets.

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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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