Note 16 - Fair Value Measurements (Details Textual) $ in Thousands	12 Months Ended
Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Debt Securities, Available-for-Sale, Amortized Cost, Total	$ 537,912	$ 514,801
Debt Securities, Available-for-Sale, Total	$ 476,091	522,566
Corporate Debt Securities [Member]
Debt Securities, Available-for-sale, Number of Securities	29
Debt Securities, Available-for-Sale, Amortized Cost, Total	$ 33,630	31,300
Debt Securities, Available-for-Sale, Total	$ 30,672	$ 32,063
Debt Securities, Available-for-sale, Level 3 to Level 2 Transfers	1	8
Inactive Corporate Debt Securities [Member]
Debt Securities, Available-for-sale, Number of Securities	6

Number available for sale debt securities transferred from Level 3 to Level 2.

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- Definition

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

+ References

No definition available.

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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
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27161-111563

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=124258926&loc=SL82898722-210454

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- Definition

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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(6))
-URI https://asc.fasb.org/extlink&oid=126897435&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
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-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=124258926&loc=SL82898722-210454

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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-Section 45
-Paragraph 1
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=124260329&loc=d3e26610-111562

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (aa)
-URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27161-111563

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