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Note 2 - Securities - Summary of Amortized Costs and Fair Values of Securities (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Sep. 30, 2022	Dec. 31, 2021
Debt Securities, Available-for-Sale, Amortized Cost, Total	$ 186,826	$ 82,200	$ 290,058
Gross unrealized gains, available for sale securities	99		2,033
Gross unrealized losses, available for sale securities	(24,018)		(2,596)
Debt Securities, Available-for-Sale, Total	162,907	$ 74,400	289,495
Amortized cost, held to maturity securities	153,158		33,441
Gross unrealized gains, held to maturity securities	0		242
Gross unrealized losses, held to maturity securities	(11,361)		(66)
Fair value, held to maturity securities	141,797		33,617
Amortized cost	339,984		323,499
Gross unrealized gains	99		2,275
Gross unrealized losses	(35,379)		(2,662)
Total securities, fair value	304,704		323,112
US Treasury Securities [Member]
Debt Securities, Available-for-Sale, Amortized Cost, Total	12,469		39,871
Gross unrealized gains, available for sale securities	0		37
Gross unrealized losses, available for sale securities	(1,239)		(250)
Debt Securities, Available-for-Sale, Total	11,229		39,658
Amortized cost, held to maturity securities	38,211
Gross unrealized gains, held to maturity securities	0
Gross unrealized losses, held to maturity securities	(568)
Fair value, held to maturity securities	37,643
US Agency and Mortgage-backed Securities [Member]
Debt Securities, Available-for-Sale, Amortized Cost, Total	109,971		177,131
Gross unrealized gains, available for sale securities	95		1,085
Gross unrealized losses, available for sale securities	(13,149)		(1,837)
Debt Securities, Available-for-Sale, Total	96,918		176,379
Amortized cost, held to maturity securities	99,374		26,392
Gross unrealized gains, held to maturity securities	0		124
Gross unrealized losses, held to maturity securities	(9,189)		(53)
Fair value, held to maturity securities	90,185		26,463
US States and Political Subdivisions Debt Securities [Member]
Debt Securities, Available-for-Sale, Amortized Cost, Total	64,386		71,037
Gross unrealized gains, available for sale securities	4		910
Gross unrealized losses, available for sale securities	(9,630)		(509)
Debt Securities, Available-for-Sale, Total	54,760		71,438
Amortized cost, held to maturity securities	12,573		7,049
Gross unrealized gains, held to maturity securities	0		118
Gross unrealized losses, held to maturity securities	(1,252)		(13)
Fair value, held to maturity securities	11,321		7,154
Corporate Debt Securities [Member]
Debt Securities, Available-for-Sale, Amortized Cost, Total			2,019
Gross unrealized gains, available for sale securities			1
Gross unrealized losses, available for sale securities			0
Debt Securities, Available-for-Sale, Total			$ 2,020
Amortized cost, held to maturity securities	3,000
Gross unrealized gains, held to maturity securities	0
Gross unrealized losses, held to maturity securities	(352)
Fair value, held to maturity securities	$ 2,648

X

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