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Note 3 - Investments - Schedule of Investments in Unrealized Loss Position (Details) - USD ($) $ in Thousands | Mar. 31, 2024 | Dec. 31, 2023
--- | --- | ---
Less than 12 months, fair value, available for sale securities | $ 79,874 | $ 58,754
Less than 12 months, unrealized loss, available for sale securities | (816) | (637)
12 months or longer, unrealized loss, fair value, available for sale securities | 165,595 | 209,362
12 months or longer, unrealized loss, available for sale securities | (29,825) | (36,064)
Available for sale securities, fair value, total | 245,469 | 268,116
Available for sale securities, unrealized losses total | (30,641) | (36,701)
Less than 12 months, fair value, held to maturity | 0 | 0
Less than 12 months, held to maturity securities | 0 | 0
12 months or longer, unrealized loss, fair value, held to maturity securities | 7,785 | 7,666
12 months or longer, unrealized loss, held to maturity securities | (715) | (834)
Held to maturity securities, fair value, total | 7,785 | 7,666
Held-to-maturity, total | (715) | (834)
Less than 12 months, fair value | 79,874 | 58,754
Less than 12 months, unrealized loss | (816) | (637)
12 months or longer, fair value | 173,380 | 217,028
12 months or longer, unrealized loss | (30,540) | (36,898)
Debt Securities, fair value, total | 253,254 | 275,782
Debt securities, unrealized loss, total | (31,356) | (37,535)
US Government Agencies Debt Securities [Member] |  |
Less than 12 months, fair value, available for sale securities | 0 | 0
Less than 12 months, unrealized loss, available for sale securities | 0 | 0
12 months or longer, unrealized loss, fair value, available for sale securities | 15,853 | 15,972
12 months or longer, unrealized loss, available for sale securities | (3,298) | (3,179)
Available for sale securities, fair value, total | 15,853 | 15,972
Available for sale securities, unrealized losses total | (3,298) | (3,179)
Corporate Debt Securities [Member] |  |
Less than 12 months, fair value, available for sale securities | 7,846 | 959
Less than 12 months, unrealized loss, available for sale securities | (154) | (41)
12 months or longer, unrealized loss, fair value, available for sale securities | 4,263 | 4,300
12 months or longer, unrealized loss, available for sale securities | (736) | (700)
Available for sale securities, fair value, total | 12,109 | 5,259
Available for sale securities, unrealized losses total | (890) | (741)
Less than 12 months, fair value, held to maturity | 0 | 0
Less than 12 months, held to maturity securities | 0 | 0
12 months or longer, unrealized loss, fair value, held to maturity securities | 7,785 | 7,666
12 months or longer, unrealized loss, held to maturity securities | (715) | (834)
Held to maturity securities, fair value, total | 7,785 | 7,666
Held-to-maturity, total | (715) | (834)
Municipal Bonds [Member] |  |
Less than 12 months, fair value, available for sale securities | 1,279 | 3,922
Less than 12 months, unrealized loss, available for sale securities | (7) | (23)
12 months or longer, unrealized loss, fair value, available for sale securities | 71,256 | 113,577
12 months or longer, unrealized loss, available for sale securities | (12,715) | (19,375)
Available for sale securities, fair value, total | 72,535 | 117,499
Available for sale securities, unrealized losses total | (12,722) | (19,398)
Collateralized Mortgage-Backed Securities [Member] |  |
Less than 12 months, fair value, available for sale securities | 25,189 | 20,662
Less than 12 months, unrealized loss, available for sale securities | (63) | (113)
12 months or longer, unrealized loss, fair value, available for sale securities | 66,593 | 67,376
12 months or longer, unrealized loss, available for sale securities | (11,901) | (11,732)
Available for sale securities, fair value, total | 91,782 | 88,038
Available for sale securities, unrealized losses total | (11,964) | (11,845)
U.S. Small Business Administration Securities [Member] |  |
Less than 12 months, fair value, available for sale securities | 45,560 | 33,211
Less than 12 months, unrealized loss, available for sale securities | (592) | (460)
12 months or longer, unrealized loss, fair value, available for sale securities | 7,630 | 8,137
12 months or longer, unrealized loss, available for sale securities | (1,175) | (1,078)
Available for sale securities, fair value, total | 53,190 | 41,348
Available for sale securities, unrealized losses total | $ (1,767) | $ (1,538)

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