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Note 2 - Securities - Available-for-sale Securities (Details) - USD ($)	Dec. 31, 2022	Dec. 31, 2021
Amortized cost	$ 685,646,000	$ 597,463,000
Securities available for sale, gross unrealized gains	571,000	5,238,000
Securities available for sale, gross unrealized losses	(83,281,000)	(9,958,000)
Fair value	602,936,000	592,743,000
US Government Agencies Debt Securities [Member]
Amortized cost	453,836,000	398,874,000
Securities available for sale, gross unrealized gains	0	266,000
Securities available for sale, gross unrealized losses	(65,092,000)	(8,769,000)
Fair value	388,744,000	390,371,000
Collateralized Mortgage-Backed Securities [Member]
Amortized cost	38,002,000	41,906,000
Securities available for sale, gross unrealized gains	19,000	549,000
Securities available for sale, gross unrealized losses	(6,068,000)	(652,000)
Fair value	31,953,000	41,803,000
Municipal General Obligation Bonds [Member]
Amortized cost	163,041,000	133,894,000
Securities available for sale, gross unrealized gains	450,000	4,092,000
Securities available for sale, gross unrealized losses	(9,058,000)	(392,000)
Fair value	154,433,000	137,594,000
Municipal Revenue Bonds [Member]
Amortized cost	30,267,000	22,289,000
Securities available for sale, gross unrealized gains	102,000	331,000
Securities available for sale, gross unrealized losses	(3,063,000)	(145,000)
Fair value	27,306,000	22,475,000
Other Debt and Equity Securities [Member]
Amortized cost	500,000	500,000
Securities available for sale, gross unrealized gains	0	0
Securities available for sale, gross unrealized losses	0	0
Fair value	$ 500,000	$ 500,000

X

- Definition

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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