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Note 2 - Securities - Investments in an Unrealized Loss Position That Were Temporarily Impaired (Details) - USD ($) $ in Thousands | Dec. 31, 2022 | Dec. 31, 2021
--- | --- | ---
Less than 12 months, fair value, available for sale securities | $ 61,012 | $ 174,217
Less than 12 months, unrealized (loss), available for sale securities | (5,458) | (2,085)
12 months or more, fair value, available for sale securities | 90,892 | 15,758
12 months or more, unrealized (loss), available for sale securities | (18,560) | (511)
Total, fair value, available for sale securities | 151,904 | 189,975
Total, unrealized (loss), available for sale securities | (24,018) | (2,596)
Less than 12 months, fair value, held to maturity securities | 88,617 | 6,410
Less than 12 months, fair value, held to maturity securities | (8,466) | (66)
12 months or more, fair value, held to maturity securities | 53,181 | 0
12 months or more, unrealized (loss), available for sale securities | (2,895) | 0
Total, fair value, held to maturity securities | 141,798 | 6,410
Total, unrealized (loss), held to maturity securities | (11,361) | (66)
Less than 12 months, fair value | 149,629 | 180,627
Less than 12 months, fair value, | (13,924) | (2,151)
12 months or more, fair value | 144,073 | 15,758
12 months or more, unrealized (loss) | (21,455) | (511)
Total, fair value | 293,702 | 196,385
Total, unrealized (loss) | (35,379) | (2,662)
US Treasury Securities [Member] |  |
Less than 12 months, fair value, available for sale securities | 9,041 | 29,656
Less than 12 months, unrealized (loss), available for sale securities | (932) | (250)
12 months or more, fair value, available for sale securities | 2,188 | 0
12 months or more, unrealized (loss), available for sale securities | (307) | 0
Total, fair value, available for sale securities | 11,229 | 29,656
Total, unrealized (loss), available for sale securities | (1,239) | (250)
Less than 12 months, fair value, held to maturity securities | 19,302 |
Less than 12 months, fair value, held to maturity securities | (258) |
12 months or more, fair value, held to maturity securities | 18,342 |
12 months or more, unrealized (loss), available for sale securities | (310) |
Total, fair value, held to maturity securities | 37,644 |
Total, unrealized (loss), held to maturity securities | (568) |
US Agency and Mortgage-backed Securities [Member] |  |
Less than 12 months, fair value, available for sale securities | 27,282 | 109,950
Less than 12 months, unrealized (loss), available for sale securities | (1,945) | (1,335)
12 months or more, fair value, available for sale securities | 62,342 | 14,749
12 months or more, unrealized (loss), available for sale securities | (11,204) | (502)
Total, fair value, available for sale securities | 89,624 | 124,699
Total, unrealized (loss), available for sale securities | (13,149) | (1,837)
Less than 12 months, fair value, held to maturity securities | 58,019 | 5,411
Less than 12 months, fair value, held to maturity securities | (6,848) | (53)
12 months or more, fair value, held to maturity securities | 32,167 | 0
12 months or more, unrealized (loss), available for sale securities | (2,341) | 0
Total, fair value, held to maturity securities | 90,186 | 5,411
Total, unrealized (loss), held to maturity securities | (9,189) | (53)
US States and Political Subdivisions Debt Securities [Member] |  |
Less than 12 months, fair value, available for sale securities | 24,689 | 34,611
Less than 12 months, unrealized (loss), available for sale securities | (2,581) | (500)
12 months or more, fair value, available for sale securities | 26,362 | 1,009
12 months or more, unrealized (loss), available for sale securities | (7,049) | (9)
Total, fair value, available for sale securities | 51,051 | 35,620
Total, unrealized (loss), available for sale securities | (9,630) | (509)
Less than 12 months, fair value, held to maturity securities | 8,648 | 999
Less than 12 months, fair value, held to maturity securities | (1,008) | (13)
12 months or more, fair value, held to maturity securities | 2,672 | 0
12 months or more, unrealized (loss), available for sale securities | (244) | 0
Total, fair value, held to maturity securities | 11,320 | 999
Total, unrealized (loss), held to maturity securities | (1,252) | $ (13)
Corporate Debt Securities [Member] |  |
Less than 12 months, fair value, held to maturity securities | 2,648 |
Less than 12 months, fair value, held to maturity securities | (352) |
12 months or more, fair value, held to maturity securities | 0 |
12 months or more, unrealized (loss), available for sale securities | 0 |
Total, fair value, held to maturity securities | 2,648 |
Total, unrealized (loss), held to maturity securities | $ (352) |

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