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Note 2 - Securities - Summary of Amortized Costs and Fair Values of Securities (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Jan. 01, 2023	Dec. 31, 2022	Sep. 01, 2022
Debt Securities, Available-for-Sale, Amortized Cost	$ 176,499		$ 186,826	$ 82,200
Gross unrealized gains, available for sale securities	64		99
Gross unrealized losses, available for sale securities	(28,388)		(24,018)
Debt Securities, Available-for-Sale, Total	148,175		162,907	$ 74,400
Securities available for sale, AFS	0
Amortized cost, held to maturity securities	150,079		153,158
Gross unrealized gains, held to maturity securities	0		0
Gross unrealized losses, held to maturity securities	(15,220)		(11,361)
Fair value, held to maturity securities	134,859		141,797
Securities available for sale, HTM	(131)		0
Amortized cost	326,578		339,984
Gross unrealized gains	64		99
Gross unrealized losses	(43,608)		(35,379)
Total securities, fair value	283,034		304,704
Total securities, allowance for credit loss	(131)
US Treasury Securities [Member]
Debt Securities, Available-for-Sale, Amortized Cost	12,474		12,468
Gross unrealized gains, available for sale securities	0		0
Gross unrealized losses, available for sale securities	(1,361)		(1,239)
Debt Securities, Available-for-Sale, Total	11,113		11,229
Securities available for sale, AFS	0
Amortized cost, held to maturity securities	38,862		38,211
Gross unrealized gains, held to maturity securities	0		0
Gross unrealized losses, held to maturity securities	(734)		(568)
Fair value, held to maturity securities	38,128		37,643
Securities available for sale, HTM	0		0
US Agency and Mortgage-backed Securities [Member]
Debt Securities, Available-for-Sale, Amortized Cost	99,894		109,972
Gross unrealized gains, available for sale securities	60		95
Gross unrealized losses, available for sale securities	(15,660)		(13,149)
Debt Securities, Available-for-Sale, Total	84,294		96,918
Securities available for sale, AFS	0
Amortized cost, held to maturity securities	96,563		99,374
Gross unrealized gains, held to maturity securities	0		0
Gross unrealized losses, held to maturity securities	(12,216)		(9,189)
Fair value, held to maturity securities	84,347		90,185
Securities available for sale, HTM	0		0
US States and Political Subdivisions Debt Securities [Member]
Debt Securities, Available-for-Sale, Amortized Cost	64,131		64,386
Gross unrealized gains, available for sale securities	4		4
Gross unrealized losses, available for sale securities	(11,367)		(9,630)
Debt Securities, Available-for-Sale, Total	52,768		54,760
Securities available for sale, AFS	0
Amortized cost, held to maturity securities	11,654		12,573
Gross unrealized gains, held to maturity securities	0		0
Gross unrealized losses, held to maturity securities	(1,706)		(1,252)
Fair value, held to maturity securities	9,948		11,321
Securities available for sale, HTM	0		0
Corporate Debt Securities [Member]
Amortized cost, held to maturity securities	3,000		3,000
Gross unrealized gains, held to maturity securities	0		0
Gross unrealized losses, held to maturity securities	(564)		(352)
Fair value, held to maturity securities	2,436		2,648
Securities available for sale, HTM	$ (131)	$ 0	$ 0

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