Note 2 - Securities - Investments in an Unrealized Loss Position That Were Temporarily Impaired (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Less than 12 months, fair value, available for sale securities	$ 14,676	$ 28,284
Less than 12 months, unrealized (loss), available for sale securities	(78)	(372)
12 months or more, fair value, available for sale securities	124,003	127,264
12 months or more, unrealized (loss), available for sale securities	(15,724)	(21,760)
Total, fair value, available for sale securities	138,679	155,548
Total, unrealized (loss), available for sale securities	(15,802)	(22,132)
US Treasury Securities [Member]
Less than 12 months, fair value, available for sale securities	4,958	0
Less than 12 months, unrealized (loss), available for sale securities	0	0
12 months or more, fair value, available for sale securities	12,072	11,688
12 months or more, unrealized (loss), available for sale securities	(418)	(795)
Total, fair value, available for sale securities	17,030	11,688
Total, unrealized (loss), available for sale securities	(418)	(795)
US Agency and Mortgage-backed Securities [Member]
Less than 12 months, fair value, available for sale securities	9,718	23,445
Less than 12 months, unrealized (loss), available for sale securities	(78)	(237)
12 months or more, fair value, available for sale securities	63,649	67,800
12 months or more, unrealized (loss), available for sale securities	(8,833)	(12,261)
Total, fair value, available for sale securities	73,367	91,245
Total, unrealized (loss), available for sale securities	(8,911)	(12,498)
US States and Political Subdivisions Debt Securities [Member]
Less than 12 months, fair value, available for sale securities	0	4,839
Less than 12 months, unrealized (loss), available for sale securities	0	(135)
12 months or more, fair value, available for sale securities	48,282	47,776
12 months or more, unrealized (loss), available for sale securities	(6,473)	(8,704)
Total, fair value, available for sale securities	48,282	52,615
Total, unrealized (loss), available for sale securities	$ (6,473)	$ (8,839)

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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