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Summary of Significant Accounting Policies (Details Textual) $ in Thousands	3 Months Ended				9 Months Ended	12 Months Ended
	Sep. 30, 2015 USD ($)	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014 USD ($)	Jun. 30, 2015 USD ($)	Sep. 30, 2015 USD ($) Customer	Sep. 30, 2014 USD ($) Customer	Sep. 30, 2013 USD ($) Customer Segment
Accounting Policies [Abstract]
Number of operating segments \| Segment								2
Allowance for doubtful accounts	$ 1,127					$ 1,127	$ 333
Accounts receivable, written off						0	158
Provision for doubtful accounts						$ 487	$ 9	$ 81
Percentage of inventory estimated using LIFO method	38.00%					38.00%	40.00%
Reserve for obsolete and excess inventory	$ 3,022					$ 3,022	$ 1,407
Depreciation expense						6,048	4,735	3,649
Concentration Risk [Line Items]
Increase (Decrease) in Workers' Compensation Liabilities				$ 400
Cost of goods sold						93,569	94,325	88,643
Selling, general and administrative expenses						19,167	15,084	11,605
Subsidiaries
Concentration Risk [Line Items]
Rental income, quarterly installment						103
Carrying value of property in corporate identifiable assets	$ 1,570					1,570	1,643
Rental income						$ 413	413	413
Deferred income tax reversed due to change in assertion					$ 992
Minimum
Concentration Risk [Line Items]
Intangible assets amortized over useful lives (in years)						1 year
Maximum
Concentration Risk [Line Items]
Intangible assets amortized over useful lives (in years)						10 years
Interest Rate Swap
Concentration Risk [Line Items]
Interest rate swap agreement amount							4,000
Building and Building Improvements \| Minimum
Concentration Risk [Line Items]
Property, plant and equipment, useful life (in years)						5 years
Building and Building Improvements \| Maximum
Concentration Risk [Line Items]
Property, plant and equipment, useful life (in years)						40 years
Machinery and equipment
Concentration Risk [Line Items]
Impairment charge								72
Machinery and equipment \| Minimum
Concentration Risk [Line Items]
Property, plant and equipment, useful life (in years)						3 years
Machinery and equipment \| Maximum
Concentration Risk [Line Items]
Property, plant and equipment, useful life (in years)						20 years
Software \| Minimum
Concentration Risk [Line Items]
Property, plant and equipment, useful life (in years)						3 years
Software \| Maximum
Concentration Risk [Line Items]
Property, plant and equipment, useful life (in years)						7 years
Scenario, Previously Reported
Cost of goods sold							93,729	87,986
Selling, general and administrative expenses							$ 15,680	$ 12,262
Cost of Sales
Immaterial correction increase (decrease), percent	(1.20%)	0.40%	3.60%	0.50%
Selling, General and Administrative Expenses
Immaterial correction increase (decrease), percent	(3.20%)	(3.40%)	(4.30%)	5.30%
Customer Concentration Risk \| Sales Revenue, Net
Concentration Risk [Line Items]
Number of major customer \| Customer						1	3	3
Percentage of concentration risk						12.00%	37.00%	39.00%
Customer Concentration Risk \| Sales Revenue, Net \| Total Customers And Their Subcontractors
Concentration Risk [Line Items]
Number of major customer \| Customer						2	3	4
Percentage of concentration risk						38.00%	50.00%	60.00%
Customer Concentration Risk \| Sales Revenue, Net \| Major Customer One And Their Subcontractors
Concentration Risk [Line Items]
Percentage of concentration risk						22.00%	24.00%	21.00%
Customer Concentration Risk \| Sales Revenue, Net \| Major Customer Two And Their Subcontractors
Concentration Risk [Line Items]
Percentage of concentration risk						16.00%	15.00%	16.00%
Customer Concentration Risk \| Sales Revenue, Net \| Major Customer Three And Their Subcontractors
Concentration Risk [Line Items]
Percentage of concentration risk							11.00%	13.00%
Customer Concentration Risk \| Sales Revenue, Net \| Major Customer Four And Their Subcontractors
Concentration Risk [Line Items]
Percentage of concentration risk								10.00%
Customer Concentration Risk \| Sales Revenue, Net \| Customer One
Concentration Risk [Line Items]
Percentage of concentration risk							14.00%	16.00%
Customer Concentration Risk \| Sales Revenue, Net \| Customer Two
Concentration Risk [Line Items]
Percentage of concentration risk							12.00%	13.00%
Customer Concentration Risk \| Sales Revenue, Net \| Customer Three
Concentration Risk [Line Items]
Percentage of concentration risk							11.00%	10.00%
Customer Concentration Risk \| Accounts Receivable
Concentration Risk [Line Items]
Number of major customer \| Customer							2
Customer Concentration Risk \| Accounts Receivable \| Total Customers And Their Subcontractors
Concentration Risk [Line Items]
Number of major customer \| Customer						2	2
Customer Concentration Risk \| Accounts Receivable \| Major Customer One And Their Subcontractors
Concentration Risk [Line Items]
Percentage of concentration risk						18.00%	27.00%
Customer Concentration Risk \| Accounts Receivable \| Major Customer Two And Their Subcontractors
Concentration Risk [Line Items]
Percentage of concentration risk						16.00%	14.00%
Customer Concentration Risk \| Accounts Receivable \| Customer One
Concentration Risk [Line Items]
Number of major customer \| Customer						1
Percentage of concentration risk						11.00%	13.00%
Customer Concentration Risk \| Accounts Receivable \| Customer Two
Concentration Risk [Line Items]
Percentage of concentration risk							10.00%