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Note 2 - Securities (Details Textual) $ in Thousands	12 Months Ended
	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Debt Securities, Held-to-Maturity, Fair Value, Total	$ 353,901
Other-than-temporary Impairment Loss, Debt Securities, Available-for-Sale	$ 0	$ 0
Debt Securities, Available-for-Sale, Unrealized Loss Position, Number of Positions	611	247
US Treasury Securities [Member] | AA or Better [Member]
Debt Securities, Percent	100.00%
US States and Political Subdivisions Debt Securities [Member]
Debt Securities, Held-to-Maturity, Fair Value, Total	$ 162,536
US States and Political Subdivisions Debt Securities [Member] | AA or Better [Member]
Debt Securities, Percent	86.00%
Collateralized Mortgage-Backed Securities [Member]
Debt Securities, Held-to-Maturity, Fair Value, Total	$ 170,605
Collateralized Mortgage-Backed Securities [Member] | AA or Better [Member]
Debt Securities, Percent	100.00%
Collateralized Mortgage-Backed Securities [Member] | AA [Member]
Debt Securities, Percent	38.00%
Collateralized Mortgage-Backed Securities [Member] | AAA [Member]
Debt Securities, Percent	31.00%
Collateralized Mortgage-Backed Securities [Member] | Unrated [Member]
Debt Securities, Percent	13.00%
Reclassified From Available-for-sale Securities [Member]
Debt Securities, Held-to-Maturity, Fair Value, Total	$ 428,400
OCI, Debt Securities, Available-for-Sale, Transfer to Held-to-Maturity, Adjustment from AOCI for Amortization of Gain (Loss), after Tax	2,700
OCI, Debt Securities, Available-for-Sale, Transfer to Held-to-Maturity, Adjustment from AOCI Unamortized, After Tax	$ 2,400

X

- Definition

The percent of debt securities.

+ References

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+ References

No definition available.

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- Definition

Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 6
-Subparagraph (b)(3)
-URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27290-111563

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 50
-Paragraph 4
-Subparagraph (b)(3)
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- Definition

Fair value of investment in debt security measured at amortized cost (held-to-maturity).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (aa)
-URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27232-111563

Reference 2: 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 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5A
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126970911&loc=SL120269820-111563

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+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 14A
-URI https://asc.fasb.org/extlink&oid=126968391&loc=SL7669686-108580

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 35
-Paragraph 10B
-Subparagraph (d)
-URI https://asc.fasb.org/extlink&oid=124260725&loc=SL120268667-111560

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Amount of other-than-temporary impairment (OTTI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), recognized in earnings and other comprehensive loss (OCI).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 8A
-URI https://asc.fasb.org/extlink&oid=124260329&loc=SL6284422-111562

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