Note 2 - Investment Securities - Available-for-sale Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Securities available-for-sale, amortized cost	$ 773,658	$ 801,371
Securities available-for-sale, unrealized gains	226	429
Securities available-for-sale, unrealized losses	(81,086)	(79,689)
Securities available-for-sale, fair value	692,798	722,111
US Government-sponsored Enterprises Debt Securities [Member]
Securities available-for-sale, amortized cost	72,672	75,459
Securities available-for-sale, unrealized gains	108	97
Securities available-for-sale, unrealized losses	(2,700)	(2,737)
Securities available-for-sale, fair value	70,080	72,819
Mortgage-Backed Security, Issued by US Government-Sponsored Enterprise [Member]
Securities available-for-sale, amortized cost	582,582	602,261
Securities available-for-sale, unrealized gains	113	322
Securities available-for-sale, unrealized losses	(68,352)	(67,576)
Securities available-for-sale, fair value	514,343	535,007
US States and Political Subdivisions Debt Securities [Member]
Securities available-for-sale, amortized cost	117,864	123,083
Securities available-for-sale, unrealized gains	5	10
Securities available-for-sale, unrealized losses	(9,996)	(9,339)
Securities available-for-sale, fair value	107,873	113,754
Other Debt Obligations [Member]
Securities available-for-sale, amortized cost	540	568
Securities available-for-sale, unrealized gains	0	0
Securities available-for-sale, unrealized losses	(38)	(37)
Securities available-for-sale, fair value	$ 502	$ 531

Amount, before tax, of unrealized gain 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).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

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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).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-2

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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479130/326-30-45-1

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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S45
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477657/942-210-S45-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478478/942-210-S50-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(6))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
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-SubTopic 30
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-Section 45
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-Publisher FASB
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