Note 16 - Share-based Compensation - Summary of Share-based Compensation Expense (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2021	Sep. 30, 2020
Share-based Payment Arrangement, Expense	$ 1,424	$ 980
Cost of Sales [Member]
Share-based Payment Arrangement, Expense	40	20
Selling, General and Administrative Expenses [Member]
Share-based Payment Arrangement, Expense	1,344	939
Research and Development Expense [Member]
Share-based Payment Arrangement, Expense	$ 40	$ 21

Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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