Summary of Significant Accounting Policies - Narrative (Details) $ in Thousands	12 Months Ended
Sep. 30, 2022 USD ($) customer shares	Sep. 30, 2021 USD ($) customer shares
Accounting Policies [Line Items]
Allowance for doubtful accounts	$ 111	$ 167
Accounts receivable, allowance for credit loss, recovery		9
Accounts receivable, written off	53
Bad debt benefit	$ 3	$ 91
Percentage of inventory estimated using LIFO method	42.00%	39.00%
Net realizable value reserves	$ 1,538	$ 325
Depreciation expense	$ 6,035	$ 6,651
Anti-dilutive weighted-average common shares excluded from calculation of diluted earnings per share (in shares) \| shares	270,000	412,000
Restricted shares
Accounting Policies [Line Items]
Anti-dilutive weighted-average common shares excluded from calculation of diluted earnings per share (in shares) \| shares	0	0
Minimum
Accounting Policies [Line Items]
Finite-lived intangible asset, useful life (in years)	1 year
Maximum
Accounting Policies [Line Items]
Finite-lived intangible asset, useful life (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
Leasehold Improvements \| Minimum
Accounting Policies [Line Items]
Property, plant and equipment, useful life (in years)	6 years
Leasehold Improvements \| Maximum
Accounting Policies [Line Items]
Property, plant and equipment, useful life (in years)	15 years
Customer Concentration Risk \| Sales Revenue, Net \| Customer One
Accounting Policies [Line Items]
Percentage of concentration risk	11.00%
Number of major customers \| customer	1
Customer Concentration Risk \| Sales Revenue, Net \| Two Largest Customers
Accounting Policies [Line Items]
Percentage of concentration risk	23.00%	20.00%
Number of major customers \| customer	2	2
Customer Concentration Risk \| Sales Revenue, Net \| Total Customers and Their Subcontractors
Accounting Policies [Line Items]
Percentage of concentration risk		38.00%
Number of major customers \| customer		3
Customer Concentration Risk \| Sales Revenue, Net \| Major Customer One and Their Subcontractors
Accounting Policies [Line Items]
Percentage of concentration risk	12.00%	17.00%
Customer Concentration Risk \| Sales Revenue, Net \| Major Customer Two and Their Subcontractors
Accounting Policies [Line Items]
Percentage of concentration risk	11.00%	11.00%
Customer Concentration Risk \| Sales Revenue, Net \| Major Customer Three and Their Subcontractors
Accounting Policies [Line Items]
Percentage of concentration risk		10.00%
Customer Concentration Risk \| Accounts Receivable \| Total Customers and Their Subcontractors
Accounting Policies [Line Items]
Number of major customers \| customer	4	1
Customer Concentration Risk \| Accounts Receivable \| Major Customer One and Their Subcontractors
Accounting Policies [Line Items]
Percentage of concentration risk	15.00%	17.00%
Customer Concentration Risk \| Accounts Receivable \| Major Customer Two and Their Subcontractors
Accounting Policies [Line Items]
Percentage of concentration risk	11.00%
Customer Concentration Risk \| Accounts Receivable \| Major Customer Three and Their Subcontractors
Accounting Policies [Line Items]
Percentage of concentration risk	11.00%
Customer Concentration Risk \| Accounts Receivable \| Major Customer Four and Their Subcontractors
Accounting Policies [Line Items]
Percentage of concentration risk	10.00%
Customer Concentration Risk \| Accounts Receivable \| Three Largest Customers
Accounting Policies [Line Items]
Number of major customers \| customer	3
Customer Concentration Risk \| Accounts Receivable \| Customer One
Accounting Policies [Line Items]
Percentage of concentration risk	15.00%
Customer Concentration Risk \| Accounts Receivable \| Customer Two
Accounting Policies [Line Items]
Percentage of concentration risk	11.00%
Customer Concentration Risk \| Accounts Receivable \| Customer Three
Accounting Policies [Line Items]
Percentage of concentration risk	10.00%

Inventory Valuation Reserves, Net Of Writedown

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Number of major customer.

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Amount of allowance for credit loss on accounts receivable.

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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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