Business Information - Narrative (Details) $ in Thousands	12 Months Ended
Sep. 30, 2018 USD ($) segment bargaining_unit employee	Sep. 30, 2017 USD ($)
Revenues from External Customers and Long-Lived Assets [Line Items]
Number of reportable segments \| segment	1
Identifiable assets	$ 52,654	$ 58,753
Number of employees represented by separate collective bargaining agreements \| employee	196
Number of collective bargain agreements \| bargaining_unit	2
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Identifiable assets	$ 29,595	33,114
Europe
Revenues from External Customers and Long-Lived Assets [Line Items]
Identifiable assets	23,059	25,639
Ireland and Italy
Revenues from External Customers and Long-Lived Assets [Line Items]
Identifiable assets	$ 33,507	$ 37,607
Sales Revenue, Net \| United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Concentration risk based on geographic location, percent	69.00%	63.00%
Sales Revenue, Net \| Europe
Revenues from External Customers and Long-Lived Assets [Line Items]
Concentration risk based on geographic location, percent	19.00%	27.00%
Sales Revenue, Net \| Asia
Revenues from External Customers and Long-Lived Assets [Line Items]
Concentration risk based on geographic location, percent	7.00%	2.00%

Number of Collective Bargain Units

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- Definition

Number of Employees Represented by Separate Collective Bargaining Units

+ References

No definition available.

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 41
-Subparagraph (b)
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- Definition

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.

+ References

No definition available.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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