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Note 3 - Investments - Schedule of Investments in Unrealized Loss Position (Details) - USD ($) $ in Thousands | Dec. 31, 2023 | Dec. 31, 2022
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Less than 12 months, fair value, available for sale securities | $ 58,754 | $ 91,176
Less than 12 months, unrealized loss, available for sale securities | (637) | (10,266)
12 months or longer, unrealized loss, fair value, available for sale securities | 209,362 | 133,700
12 months or longer, unrealized loss, available for sale securities | (36,064) | (32,323)
Available for sale securities, fair value | 268,116 | 224,876
Available for sale securities, total | (36,701) | (42,589)
Less than 12 months, fair value, held to maturity | 0 | 7,929
Less than 12 months, held to maturity securities | 0 | (571)
12 months or longer, unrealized loss, fair value, held to maturity securities | 7,666 | 0
12 months or longer, unrealized loss, held to maturity securities | (834) | 0
Held to maturity securities, fair value | 7,666 | 7,929
Held-to-maturity, total | (834) | (571)
Less than 12 months, fair value | 58,754 | 99,105
Less than 12 months, unrealized loss | (637) | (10,837)
12 months or longer, fair value | 217,028 | 133,700
12 months or longer, unrealized loss | (36,898) | (32,323)
Debt Securities, fair value | 275,782 | 232,805
Debt securities, unrealized loss | (37,535) | (43,160)
US Government Agencies Debt Securities [Member] |  |
Less than 12 months, fair value, available for sale securities | 0 | 3,823
Less than 12 months, unrealized loss, available for sale securities | 0 | (118)
12 months or longer, unrealized loss, fair value, available for sale securities | 15,972 | 13,465
12 months or longer, unrealized loss, available for sale securities | (3,179) | (3,747)
Available for sale securities, fair value | 15,972 | 17,288
Available for sale securities, total | (3,179) | (3,865)
Corporate Debt Securities [Member] |  |
Less than 12 months, fair value, available for sale securities | 959 | 2,494
Less than 12 months, unrealized loss, available for sale securities | (41) | (4)
12 months or longer, unrealized loss, fair value, available for sale securities | 4,300 | 4,026
12 months or longer, unrealized loss, available for sale securities | (700) | (975)
Available for sale securities, fair value | 5,259 | 6,520
Available for sale securities, total | (741) | (979)
Less than 12 months, fair value, held to maturity | 0 | 7,929
Less than 12 months, held to maturity securities | 0 | (571)
12 months or longer, unrealized loss, fair value, held to maturity securities | 7,666 | 0
12 months or longer, unrealized loss, held to maturity securities | (834) | 0
Held to maturity securities, fair value | 7,666 | 7,929
Held-to-maturity, total | (834) | (571)
Municipal Bonds [Member] |  |
Less than 12 months, fair value, available for sale securities | 3,922 | 44,261
Less than 12 months, unrealized loss, available for sale securities | (23) | (5,794)
12 months or longer, unrealized loss, fair value, available for sale securities | 113,577 | 73,990
12 months or longer, unrealized loss, available for sale securities | (19,375) | (17,825)
Available for sale securities, fair value | 117,499 | 118,251
Available for sale securities, total | (19,398) | (23,619)
Collateralized Mortgage-Backed Securities [Member] |  |
Less than 12 months, fair value, available for sale securities | 20,662 | 29,791
Less than 12 months, unrealized loss, available for sale securities | (113) | (3,188)
12 months or longer, unrealized loss, fair value, available for sale securities | 67,376 | 40,175
12 months or longer, unrealized loss, available for sale securities | (11,732) | (9,270)
Available for sale securities, fair value | 88,038 | 69,966
Available for sale securities, total | (11,845) | (12,458)
U.S. Small Business Administration Securities [Member] |  |
Less than 12 months, fair value, available for sale securities | 33,211 | 10,807
Less than 12 months, unrealized loss, available for sale securities | (460) | (1,162)
12 months or longer, unrealized loss, fair value, available for sale securities | 8,137 | 2,044
12 months or longer, unrealized loss, available for sale securities | (1,078) | (506)
Available for sale securities, fair value | 41,348 | 12,851
Available for sale securities, total | $ (1,538) | $ (1,668)

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