Basis of Presentation and Significant Accounting Policies -Additional information (Details)	12 Months Ended
Sep. 30, 2024 USD ($) Customer Subsidiary Segment	Sep. 30, 2023 USD ($) Customer	Sep. 30, 2022 USD ($)
Number of wholly owned subsidiaries \| Subsidiary	8
Number of additional inactive subsidiaries \| Subsidiary	1
Cash and cash equivalents retained in foreign banks	$ 627,000
Investments typical final maturity maximum year	3 years
Investments typical portfolio weighted average maturity month	18 months
Cash and cash equivalents	$ 4,945,000	$ 8,665,000
Restricted cash	345,000	854,000
Allowance for doubtful accounts for expected credit losses	65,000	65,000
Inventory Obsolescence Write Down (Recoveries)	(284,000)	288,000
Goodwill impairment charge	0	0
Shipping and handling costs	128,000	289,000
Cost of revenue	13,819,000	24,901,000
Advertising expense	454,000	512,000
Warranty reserve	76,000	132,000	$ 159,000
Impairment of long-lived assets	$ 0	0
Number of reportable segments \| Segment	2
Translation gain	$ 152,000	207,000
Shipping and Handling [Member]
Cost of revenue	$ 187,000	$ 392,000
Minimum [Member]
Property, plant and equipment, estimated useful lives	2 years
Estimated useful lives	3 years
Maximum [Member]
Property, plant and equipment, estimated useful lives	7 years
Estimated useful lives	15 years
Customer Concentration Risk [Member] \| Accounts Receivable [Member]
Number of major customers \| Customer	3	3
Customer Concentration Risk [Member] \| Accounts Receivable [Member] \| Customer 1 [Member]
Concentration risk percentage	15.00%	22.00%
Customer Concentration Risk [Member] \| Accounts Receivable [Member] \| Customer 2 [Member]
Concentration risk percentage	14.00%	10.00%
Customer Concentration Risk [Member] \| Accounts Receivable [Member] \| Customer 3 [Member]
Concentration risk percentage	11.00%	10.00%

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