Note 9 - Marketable Securities - Marketable Securities (Details) - Corporate Debt Securities [Member]	Sep. 30, 2022 USD ($)
Debt Securities, Available-for-Sale, Amortized Cost, Total	$ 989,000
Debt Securities, Available-for-Sale, Accumulated Gross Unrealized Loss, before Tax	(6,000)
Debt Securities, Available-for-Sale, Total	$ 983,000

Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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