Note 2 - Securities - Investments in an Unrealized Loss Position That Were Temporarily Impaired (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Less than 12 months, fair value, available for sale securities	$ 95,819	$ 37,624
Less than 12 months, unrealized (loss), available for sale securities	(918)	(181)
12 months or more, fair value, available for sale securities	114,973	121,440
12 months or more, unrealized (loss), available for sale securities	(14,888)	(14,642)
Total, fair value, available for sale securities	210,792	159,064
Total, unrealized (loss), available for sale securities	(15,806)	(14,823)
12 months or more, fair value, available for sale securities	114,973	121,440
US Treasury Securities [Member]
Less than 12 months, fair value, available for sale securities	29,783	10,057
Less than 12 months, unrealized (loss), available for sale securities	(338)	(13)
12 months or more, fair value, available for sale securities	12,251	12,156
12 months or more, unrealized (loss), available for sale securities	(245)	(335)
Total, fair value, available for sale securities	42,034	22,213
Total, unrealized (loss), available for sale securities	(583)	(348)
12 months or more, fair value, available for sale securities	12,251	12,156
US Agency and Mortgage-backed Securities [Member]
Less than 12 months, fair value, available for sale securities	58,881	24,346
Less than 12 months, unrealized (loss), available for sale securities	(498)	(144)
12 months or more, fair value, available for sale securities	56,716	61,732
12 months or more, unrealized (loss), available for sale securities	(8,552)	(8,443)
Total, fair value, available for sale securities	115,597	86,078
Total, unrealized (loss), available for sale securities	(9,050)	(8,587)
12 months or more, fair value, available for sale securities	56,716	61,732
US States and Political Subdivisions Debt Securities [Member]
Less than 12 months, fair value, available for sale securities	5,189	2,764
Less than 12 months, unrealized (loss), available for sale securities	(50)	(8)
12 months or more, fair value, available for sale securities	46,006	47,552
12 months or more, unrealized (loss), available for sale securities	(6,091)	(5,864)
Total, fair value, available for sale securities	51,195	50,316
Total, unrealized (loss), available for sale securities	(6,141)	(5,872)
12 months or more, fair value, available for sale securities	46,006	47,552
Corporate Debt Securities [Member]
Less than 12 months, fair value, available for sale securities	1,966	457
Less than 12 months, unrealized (loss), available for sale securities	(32)	(16)
12 months or more, fair value, available for sale securities	0	0
12 months or more, unrealized (loss), available for sale securities	0	0
Total, fair value, available for sale securities	1,966	457
Total, unrealized (loss), available for sale securities	(32)	(16)
12 months or more, fair value, available for sale securities	$ 0	$ 0

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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