Concentrations (Details) $ in Millions	12 Months Ended
Sep. 30, 2023 USD ($) item customer	Sep. 30, 2022 USD ($) customer item	Sep. 30, 2021 USD ($) customer item
Flat Panel Display Systems
Concentrations
Concentration risk threshold percentage	99.00%	98.00%	88.00%
Concentration of Credit Risk
Concentration of Credit Risk
Number of banks for maintenance of cash balances \| item	2
Revenues Net [Member] \| Customer Concentration Risk [Member]
Concentrations
Number of major annual customers	3	3	2
Revenues Net [Member] \| Customer Concentration Risk [Member] \| Five Customers
Concentrations
Number of major customers	5	5	5
Concentration risk threshold percentage	54.00%	58.00%	59.00%
Revenues Net [Member] \| Customer Concentration Risk [Member] \| Pilatus
Concentrations
Concentration risk threshold percentage	23.00%	22.00%	20.00%
Revenues Net [Member] \| Customer Concentration Risk [Member] \| ATSG
Concentrations
Concentration risk threshold percentage	12.00%	11.00%
Revenues Net [Member] \| Customer Concentration Risk [Member] \| Textron
Concentrations
Concentration risk threshold percentage	10.00%	11.00%	17.00%
Revenues Net [Member] \| Customer Concentration Risk [Member] \| Government Contractors and Agencies
Concentrations
Concentration risk threshold percentage	9.00%	14.00%	18.00%
Revenues Net [Member] \| Product Concentration Risk [Member] \| Flat Panel Display Systems
Concentrations
Concentration risk threshold percentage	99.00%	98.00%	88.00%
Revenues Net [Member] \| Product Concentration Risk [Member] \| Air Data Systems and Components
Concentrations
Concentration risk threshold percentage	1.00%	2.00%	12.00%
Accounts receivable \| Customer Concentration Risk [Member] \| Five Customers
Concentrations
Number of customers	5	5	5
Accounts receivable and contract assets \| $	$ 3.5	$ 3.3	$ 2.1
Inventory [Member] \| Supplier Concentration Risk [Member]
Concentrations
Concentration risk threshold percentage	49.00%	33.70%	14.90%
Number of major suppliers \| item	4	3	1

No definition available.

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- Definition

Represents concentration risk threshold percentage.

+ References

No definition available.

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- Definition

Represents the number of banks for maintenance of cash balances.

+ References

No definition available.

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- Definition

Number of customers accounted for 27% of accounts receivable.

+ References

No definition available.

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- Definition

Represents the number of major customers of the entity on an annual basis.

+ References

No definition available.

+ Details

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Represents the number of major customers of the entity.

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No definition available.

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- Definition

Represents the number of major suppliers of the entity.

+ References

No definition available.

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- Definition

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 954
-SubTopic 310
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
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- Definition

The total amount due to the entity within one year of the balance sheet date (or one operating cycle, if longer) from outside sources, including trade accounts receivable, notes and loans receivable, as well as any other types of receivables, net of allowances established for the purpose of reducing such receivables to an amount that approximates their net realizable value.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 852
-SubTopic 10
-Name Accounting Standards Codification
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-Paragraph 10
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