Business Information - Narrative (Details) $ in Thousands	12 Months Ended
Sep. 30, 2023 USD ($) segment bargaining_unit hourly_plant_personnel	Sep. 30, 2022 USD ($)
Revenues from External Customers and Long-Lived Assets [Line Items]
Number of operating segments \| segment	1
Identifiable assets	$ 54,519	$ 58,487
Number of employees represented by separate collective bargaining agreements \| hourly_plant_personnel	189
Number of collective bargain agreements \| bargaining_unit	3
Number of units entered into early negotiations and ratification of CBA \| bargaining_unit	2
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Identifiable assets	$ 47,261	51,801
Europe
Revenues from External Customers and Long-Lived Assets [Line Items]
Identifiable assets	7,258	6,686
Maniago
Revenues from External Customers and Long-Lived Assets [Line Items]
Identifiable assets	$ 16,460	$ 15,219
Sales Revenue, Net \| Geographic Concentration Risk \| United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Percentage of concentration risk	59.00%	72.00%
Sales Revenue, Net \| Geographic Concentration Risk \| Europe
Revenues from External Customers and Long-Lived Assets [Line Items]
Percentage of concentration risk	29.00%	19.00%
Sales Revenue, Net \| Geographic Concentration Risk \| Asia
Revenues from External Customers and Long-Lived Assets [Line Items]
Percentage of concentration risk	7.00%	6.00%
Sales Revenue, Net \| Geographic Concentration Risk \| Other North American countries
Revenues from External Customers and Long-Lived Assets [Line Items]
Percentage of concentration risk	6.00%	3.00%
Assets, Total \| Geographic Concentration Risk \| Maniago
Revenues from External Customers and Long-Lived Assets [Line Items]
Percentage of concentration risk	17.00%	16.00%

Number Of Units, Early Negotiations And Ratification For Collective Bargaining Agreements

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Number of Collective Bargain Units

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Number of Employees Represented by Separate Collective Bargaining Units

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
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Long-lived assets other than financial instruments, long-term customer relationships of a financial institution, mortgage and other servicing rights, deferred policy acquisition costs, and deferred tax assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 280
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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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