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v3.25.3

Note 1 - Summary of Significant Accounting Policies (Details Textual) $ in Thousands | 12 Months Ended
--- | ---
Sep. 30, 2025 USD ($) | Sep. 30, 2024 USD ($)
Cash and Cash Equivalent | $ 26,338 | $ 6,895
Credit Terms for Trade Receivables (Day) |  | 30 days
Extended Credit Terms for Trade Receivables (Day) |  | 60 days
Short-Term Investments | 0 | $ 30,227
Impairment of Intangible Assets, Finite-Lived | $ 0 | 2,761
Emerging Markets [Member] |  |
Impairment of Intangible Assets, Finite-Lived |  | $ 2,800
Accounts Receivable [Member] | Customer Concentration Risk [Member] |  |
Number of Major Customers | 2 | 2
Accounts Receivable [Member] | Customer Concentration Risk [Member] | Customer One [Member] |  |
Concentration Risk, Percentage | 19.10% |
Accounts and Financing Receivable, after Allowance for Credit Loss | $ 7,300 |
Accounts Receivable [Member] | Customer Concentration Risk [Member] | Customer Two [Member] |  |
Concentration Risk, Percentage |  | 16.20%
Accounts and Financing Receivable, after Allowance for Credit Loss |  | $ 2,200
Revenue Benchmark [Member] | Customer Concentration Risk [Member] | Customer One [Member] |  |
Concentration Risk, Percentage |  | 27.40%
Accounts and Financing Receivable, after Allowance for Credit Loss |  | $ 4,100
Revenue Benchmark [Member] | Customer Concentration Risk [Member] | Customer Two [Member] |  |
Concentration Risk, Percentage |  | 16.00%
Accounts and Financing Receivable, after Allowance for Credit Loss |  | $ 9,500
Revenue Benchmark [Member] | Product Concentration Risk [Member] | Thermal Film [Member] |  |
Concentration Risk, Percentage | 7.00% | 5.00%
Non-US [Member] |  |
Cash and Cash Equivalent | $ 800 |
Subsidiaries [Member] | Non-US [Member] |  |
Cash and Cash Equivalent | $ 800 |

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