Note 2 - Securities - Amortized Cost and Estimated Fair Value of Investment Securities by Contractual Maturity (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Securities available for sale, amortized cost	$ 375,183	$ 341,504
Investment securities available for sale, at fair value	326,569	344,212
Collateralized Mortgage-Backed Securities [Member]
Due within one year, amortized cost	13,762	7,827
Due within one year, estimated fair value	13,490	7,832
Due after one through five years, amortized cost	28,890	24,347
Due after one through five years, estimated fair value	27,808	24,371
Due after five through ten years, amortized cost	13,436	8,466
Due after five through ten years, estimated fair value	12,165	8,391
Due after ten years, amortized cost	133,981	100,554
Due after ten years, estimated fair value	115,491	99,376
Securities available for sale, amortized cost	190,069	141,194
Investment securities available for sale, at fair value	168,954	139,970
Investment Securities, Excluding Mortgage Backed Securities [Member]
Due within one year, amortized cost	0	0
Due within one year, estimated fair value	0	0
Due after one through five years, amortized cost	20,700	6,391
Due after one through five years, estimated fair value	18,957	6,289
Due after five through ten years, amortized cost	64,211	79,679
Due after five through ten years, estimated fair value	57,523	80,807
Due after ten years, amortized cost	100,203	114,240
Due after ten years, estimated fair value	81,135	117,146
Securities available for sale, amortized cost	185,114	200,310
Investment securities available for sale, at fair value	$ 157,615	$ 204,242

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

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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+ 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
-SubTopic 30
-Section 45
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=124258926&loc=SL82898722-210454

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-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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