Note 2 - Investment Securities - Summary of Held-to-maturity Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Amortized cost	$ 406,590	$ 0
Gross unrealized gains	0
Gross unrealized losses	31,298
Fair value	375,292	$ 0
US Government Agencies Debt Securities [Member]
Amortized cost	4,002
Gross unrealized gains	0
Gross unrealized losses	367
Fair value	3,635
Collateralized Mortgage-Backed Securities [Member]
Amortized cost	309,748
Gross unrealized gains	0
Gross unrealized losses	24,654
Fair value	285,094
State, County and Municipal [Member]
Amortized cost	92,840
Gross unrealized gains	0
Gross unrealized losses	6,277
Fair value	$ 86,563

Amount, after allowance for credit loss, of investment in debt security measured at amortized cost (held-to-maturity).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (d)
-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 45
-Paragraph 1
-Subparagraph (b)
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Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (f)
-URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27232-111563

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

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