Business Information - Narrative (Details) $ in Thousands	12 Months Ended
Sep. 30, 2021 USD ($) separate_bargaining_unit Segment hourly_plant_personnel	Sep. 30, 2020 USD ($)
Revenues from External Customers and Long-Lived Assets [Line Items]
Number of reportable segments \| Segment	1
Identifiable assets	$ 63,095	$ 66,741
Number of employees represented by separate collective bargaining agreements \| hourly_plant_personnel	177
Number of collective bargain agreements \| separate_bargaining_unit	3
Number of units entered into early negotiations and ratification of CBA \| separate_bargaining_unit	2
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Identifiable assets	$ 54,109	56,134
Europe
Revenues from External Customers and Long-Lived Assets [Line Items]
Identifiable assets	8,986	10,607
Maniago
Revenues from External Customers and Long-Lived Assets [Line Items]
Identifiable assets	$ 19,586	$ 21,989
Sales Revenue, Net \| Geographic Concentration Risk \| United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Percentage of concentration risk	66.00%	72.00%
Sales Revenue, Net \| Geographic Concentration Risk \| Europe
Revenues from External Customers and Long-Lived Assets [Line Items]
Percentage of concentration risk	18.00%	14.00%
Sales Revenue, Net \| Geographic Concentration Risk \| Asia
Revenues from External Customers and Long-Lived Assets [Line Items]
Percentage of concentration risk	8.00%	8.00%

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

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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.

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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