Operating Segments (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Mar. 31, 2015	Mar. 31, 2014	Mar. 31, 2015	Mar. 31, 2014	Sep. 30, 2014
Segment Reporting Information [Line Items]
Revenues	$ 133,752us-gaap_Revenues	$ 120,266us-gaap_Revenues	$ 270,088us-gaap_Revenues	$ 240,345us-gaap_Revenues
Cost of Services	112,044us-gaap_CostOfServices	100,240us-gaap_CostOfServices	225,676us-gaap_CostOfServices	202,202us-gaap_CostOfServices
Gross Profit	21,708us-gaap_GrossProfit	20,026us-gaap_GrossProfit	44,412us-gaap_GrossProfit	38,143us-gaap_GrossProfit
Selling, General and Administrative Expense	19,409	19,172	38,107	36,744
Loss (gain) on sale of assets	1us-gaap_GainLossOnDispositionOfAssets	(22)us-gaap_GainLossOnDispositionOfAssets	7us-gaap_GainLossOnDispositionOfAssets	(62)us-gaap_GainLossOnDispositionOfAssets
Operating Income	2,298us-gaap_OperatingIncomeLoss	876us-gaap_OperatingIncomeLoss	6,298us-gaap_OperatingIncomeLoss	1,461us-gaap_OperatingIncomeLoss
Depreciation and amortization	589us-gaap_Depreciation	620us-gaap_Depreciation	1,169us-gaap_Depreciation	1,262us-gaap_Depreciation
Capital Expenditures	927	488	1,626	713
Assets	201,108us-gaap_Assets	170,343us-gaap_Assets	201,108us-gaap_Assets	170,343us-gaap_Assets	201,108us-gaap_Assets
Communications [Member]
Segment Reporting Information [Line Items]
Revenues	27,945	25,147	59,753	49,738
Cost of Services	23,170	21,006	49,680	41,665
Gross Profit	4,775	4,141	10,073	8,073
Selling, General and Administrative Expense	3,424	3,163	7,102	6,145
Loss (gain) on sale of assets	0	0	7	0
Operating Income	1,351	978	2,964	1,928
Depreciation and amortization	129	102	246	201
Capital Expenditures	278	55	470	63
Assets	27,499	25,010	27,499	25,010
Residential [Member]
Segment Reporting Information [Line Items]
Revenues	50,169	42,181	98,762	83,393
Cost of Services	40,503	34,529	79,908	68,323
Gross Profit	9,666	7,652	18,854	15,070
Selling, General and Administrative Expense	7,731	6,932	15,032	13,414
Loss (gain) on sale of assets	4	(1)	4	(41)
Operating Income	1,931	721	3,818	1,697
Depreciation and amortization	119	118	242	241
Capital Expenditures	124	158	193	163
Assets	37,898	36,170	37,898	36,170
Commercial & Industrial [Member]
Segment Reporting Information [Line Items]
Revenues	44,505	42,336	88,272	83,565
Cost of Services	39,686	36,484	78,169	73,799
Gross Profit	4,819	5,852	10,103	9,766
Selling, General and Administrative Expense	3,791	4,243	7,378	7,722
Loss (gain) on sale of assets	(1)	(21)	(2)	(24)
Operating Income	1,029	1,630	2,727	2,068
Depreciation and amortization	67	66	135	133
Capital Expenditures	159	40	167	95
Assets	46,793	45,169	46,793	45,169
Infrastructure Solutions [Member]
Segment Reporting Information [Line Items]
Revenues	11,133	10,602	23,301	23,649
Cost of Services	8,685	8,221	17,919	18,415
Gross Profit	2,448	2,381	5,382	5,234
Selling, General and Administrative Expense	2,313	2,295	4,332	4,683
Loss (gain) on sale of assets	(2)	0	(2)	3
Operating Income	137	86	1,052	548
Depreciation and amortization	204	217	405	484
Capital Expenditures	366	235	657	277
Assets	28,292	27,611	28,292	27,611
Corporate [Member]
Segment Reporting Information [Line Items]
Revenues	0	0	0	0
Cost of Services	0	0	0	0
Gross Profit	0	0	0	0
Selling, General and Administrative Expense	2,150	2,539	4,263	4,780
Loss (gain) on sale of assets	0	0	0	0
Operating Income	(2,150)	(2,539)	(4,263)	(4,780)
Depreciation and amortization	70	117	141	203
Capital Expenditures	0	0	139	115
Assets	$ 60,626	$ 36,383	$ 60,626	$ 36,383

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.

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Total costs related to services rendered by an entity during the reporting period.

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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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Amount of gain (loss) on sale or disposal of property, plant and equipment assets, excluding oil and gas property and timber property.

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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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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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