Note 2 - Securities - Investments in an Unrealized Loss Position That Were Temporarily Impaired (Details) - USD ($) $ in Thousands	Mar. 31, 2026	Dec. 31, 2025
Less than 12 months, fair value, available for sale securities	$ 75,250	$ 37,624
Less than 12 months, unrealized (loss), available for sale securities	(621)	(181)
12 months or more, fair value, available for sale securities	117,840	121,440
12 months or more, unrealized (loss), available for sale securities	(15,696)	(14,642)
Total, fair value, available for sale securities	193,090	159,064
Total, unrealized (loss), available for sale securities	(16,317)	(14,823)
12 months or more, fair value, available for sale securities	117,840	121,440
US Treasury Securities [Member]
Less than 12 months, fair value, available for sale securities	24,950	10,057
Less than 12 months, unrealized (loss), available for sale securities	(170)	(13)
12 months or more, fair value, available for sale securities	12,185	12,156
12 months or more, unrealized (loss), available for sale securities	(308)	(335)
Total, fair value, available for sale securities	37,135	22,213
Total, unrealized (loss), available for sale securities	(478)	(348)
12 months or more, fair value, available for sale securities	12,185	12,156
US Agency and Mortgage-backed Securities [Member]
Less than 12 months, fair value, available for sale securities	42,253	24,346
Less than 12 months, unrealized (loss), available for sale securities	(363)	(144)
12 months or more, fair value, available for sale securities	59,916	61,732
12 months or more, unrealized (loss), available for sale securities	(8,442)	(8,443)
Total, fair value, available for sale securities	102,169	86,078
Total, unrealized (loss), available for sale securities	(8,805)	(8,587)
12 months or more, fair value, available for sale securities	59,916	61,732
US States and Political Subdivisions Debt Securities [Member]
Less than 12 months, fair value, available for sale securities	6,573	2,764
Less than 12 months, unrealized (loss), available for sale securities	(69)	(8)
12 months or more, fair value, available for sale securities	45,739	47,552
12 months or more, unrealized (loss), available for sale securities	(6,946)	(5,864)
Total, fair value, available for sale securities	52,312	50,316
Total, unrealized (loss), available for sale securities	(7,015)	(5,872)
12 months or more, fair value, available for sale securities	45,739	47,552
Corporate Debt Securities [Member]
Less than 12 months, fair value, available for sale securities	1,474	457
Less than 12 months, unrealized (loss), available for sale securities	(19)	(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	1,474	457
Total, unrealized (loss), available for sale securities	(19)	(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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