Note 10 - Goodwill and Intangibles (Details Textual) $ in Thousands	9 Months Ended	12 Months Ended
Jun. 30, 2022 USD ($)	Sep. 30, 2021 USD ($)
Goodwill, Impairment Loss	$ 0	$ 0
Number of Patents Granted	31
Impairment of Intangible Assets (Excluding Goodwill), Total	$ 0	$ 0
Patents [Member]
Finite-Lived Intangible Asset, Useful Life (Year)	20 years

Represents the number of patents granted in the United States.

No definition available.

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- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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- Definition

Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 2
-Subparagraph (b)
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-Publisher FASB
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-Section 45
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
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-Section 55
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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-URI https://asc.fasb.org/extlink&oid=121556970&loc=d3e13816-109267

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- Definition

The amount of impairment loss recognized in the period resulting from the write-down of the carrying amount of an intangible asset (excluding goodwill) to fair value.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
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-URI https://asc.fasb.org/extlink&oid=66006027&loc=d3e16373-109275

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