Summary of Significant Accounting Policies - Additional Information (Details)	12 Months Ended
	Sep. 30, 2016 USD ($) Customer instrument Segment	Sep. 30, 2015 USD ($) Customer Segment
Accounting Policies [Line Items]
Number of operating segments | Segment	1	1
Allowance for doubtful accounts	$ 706,000	$ 1,127,000
Accounts receivable, written off	581,000	0
Bad debt expense	$ 359,000	$ 487,000
Percentage of inventory estimated using LIFO method	44.00%	38.00%
Reserve for obsolete and excess inventory	$ 3,308,000	$ 3,022,000
Property, plant and equipment, impairment	0	0
Depreciation expense	8,173,000	6,048,000
Cork, Ireland facility, accumulated depreciation	50,079,000	42,243,000
Decrease in workers' compensation expense		400,000
Research and development expense	0	0
Other long-term liabilities	$ 605,000	506,000
Interest Rate Swap | Cash Flow Hedging
Accounting Policies [Line Items]
Number of interest rate swaps | instrument	1
Interest rate swap agreement amount	$ 8,214,000
Interest rate swap fair value	30,000
Subsidiaries
Accounting Policies [Line Items]
Rental income, quarterly installment	103,000
Cork, Ireland facility, carrying value	1,496,000	1,570,000
Cork, Ireland facility, accumulated depreciation	1,437,000	1,511,000
Rental income	$ 413,000	$ 413,000
Minimum
Accounting Policies [Line Items]
Intangible assets amortized over useful lives (in years)	1 year
Maximum
Accounting Policies [Line Items]
Intangible assets amortized over useful lives (in years)	10 years
Building and Building Improvements | Minimum
Accounting Policies [Line Items]
Property, plant and equipment, useful life (in years)	5 years
Building and Building Improvements | Maximum
Accounting Policies [Line Items]
Property, plant and equipment, useful life (in years)	40 years
Machinery and Equipment | Minimum
Accounting Policies [Line Items]
Property, plant and equipment, useful life (in years)	3 years
Machinery and Equipment | Maximum
Accounting Policies [Line Items]
Property, plant and equipment, useful life (in years)	20 years
Computer Software | Minimum
Accounting Policies [Line Items]
Property, plant and equipment, useful life (in years)	3 years
Computer Software | Maximum
Accounting Policies [Line Items]
Property, plant and equipment, useful life (in years)	7 years
Customer Concentration Risk | Sales Revenue, Net
Accounting Policies [Line Items]
Percentage of concentration risk	21.00%
Number of major customer | Customer	2	1
Customer Concentration Risk | Sales Revenue, Net | Total Customers And Their Subcontractors
Accounting Policies [Line Items]
Percentage of concentration risk	46.00%	38.00%
Number of major customer | Customer	4	2
Customer Concentration Risk | Sales Revenue, Net | Major Customer One And Their Subcontractors
Accounting Policies [Line Items]
Percentage of concentration risk	12.00%	22.00%
Customer Concentration Risk | Sales Revenue, Net | Major Customer Two And Their Subcontractors
Accounting Policies [Line Items]
Percentage of concentration risk	12.00%	16.00%
Customer Concentration Risk | Sales Revenue, Net | Major Customer Three And Their Subcontractors
Accounting Policies [Line Items]
Percentage of concentration risk	11.00%
Customer Concentration Risk | Sales Revenue, Net | Major Customer Four And Their Subcontractors
Accounting Policies [Line Items]
Percentage of concentration risk	11.00%
Customer Concentration Risk | Sales Revenue, Net | Customer One
Accounting Policies [Line Items]
Percentage of concentration risk		12.00%
Customer Concentration Risk | Accounts Receivable
Accounting Policies [Line Items]
Number of major customer | Customer	2	1
Customer Concentration Risk | Accounts Receivable | Total Customers And Their Subcontractors
Accounting Policies [Line Items]
Number of major customer | Customer	4	2
Customer Concentration Risk | Accounts Receivable | Major Customer One And Their Subcontractors
Accounting Policies [Line Items]
Percentage of concentration risk	15.00%	18.00%
Customer Concentration Risk | Accounts Receivable | Major Customer Two And Their Subcontractors
Accounting Policies [Line Items]
Percentage of concentration risk	13.00%	16.00%
Customer Concentration Risk | Accounts Receivable | Major Customer Three And Their Subcontractors
Accounting Policies [Line Items]
Percentage of concentration risk	12.00%
Customer Concentration Risk | Accounts Receivable | Major Customer Four And Their Subcontractors
Accounting Policies [Line Items]
Percentage of concentration risk	11.00%
Customer Concentration Risk | Accounts Receivable | Customer One
Accounting Policies [Line Items]
Percentage of concentration risk	14.00%	11.00%
Customer Concentration Risk | Accounts Receivable | Customer Two
Accounting Policies [Line Items]
Percentage of concentration risk	11.00%
Scenario, Previously Reported
Accounting Policies [Line Items]
Reclassification of other operating liabilities		$ 506,000