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Note 6 - Investment and Equity Securities - Gross Unrealized Losses and Fair Value (Details) - USD ($) $ in Thousands	Jun. 30, 2025	Dec. 31, 2024
Less than Twelve Months, Fair Value	$ 17,067	$ 28,074
Less than Twelve Months, Gross Unrealized Losses	(728)	(904)
Twelve Months or Greater, Fair Value	133,618	128,372
Twelve Months or Greater, Gross Unrealized Losses	(28,406)	(24,577)
Total, Fair Value	150,685	156,446
Total, Gross Unrealized Losses	(29,134)	(25,481)
Subordinated Debt Securities [Member]
Less than Twelve Months, Fair Value	3,463	10,632
Less than Twelve Months, Gross Unrealized Losses	(37)	(368)
Twelve Months or Greater, Fair Value	26,596	20,770
Twelve Months or Greater, Gross Unrealized Losses	(1,404)	(1,530)
Total, Fair Value	30,059	31,402
Total, Gross Unrealized Losses	(1,441)	(1,898)
Nontaxable Municipal Bonds [Member]
Less than Twelve Months, Fair Value	12,246	15,456
Less than Twelve Months, Gross Unrealized Losses	(649)	(487)
Twelve Months or Greater, Fair Value	102,212	102,484
Twelve Months or Greater, Gross Unrealized Losses	(26,375)	(22,318)
Total, Fair Value	114,458	117,940
Total, Gross Unrealized Losses	(27,024)	(22,805)
Mortgage-Backed Security, Issued by US Government-Sponsored Enterprise [Member]
Less than Twelve Months, Fair Value	1,358	1,986
Less than Twelve Months, Gross Unrealized Losses	(42)	(49)
Twelve Months or Greater, Fair Value	4,810	5,118
Twelve Months or Greater, Gross Unrealized Losses	(627)	(729)
Total, Fair Value	6,168	7,104
Total, Gross Unrealized Losses	$ (669)	$ (778)

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