Note 8 - Supplementary Balance Sheet Information - Schedule of Warranty and Retrofit Costs (Details) - USD ($) $ in Thousands	6 Months Ended
Mar. 31, 2025	Mar. 31, 2024
Balance at beginning of period	$ 5,213	$ 3,974
Accruals for warranties during the period	698	1,371
Costs incurred during the period	(674)	(650)
Balance at end of period	$ 5,237	$ 4,695

Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(15)(5))
-Publisher FASB
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 460
-SubTopic 10
-Name Accounting Standards Codification
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-Paragraph 4
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-Publisher FASB
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 460
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 460
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482425/460-10-50-8

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- Definition

Amount of decrease in the standard and extended product warranty accrual from payments made in cash or in kind to satisfy claims under the terms of the standard and extended product warranty.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 460
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 8
-Subparagraph (c)(2)
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-URI https://asc.fasb.org/1943274/2147482425/460-10-50-8

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- Definition

Amount of increase in the standard and extended product warranty accrual from warranties issued.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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