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Note 3 - Investments - Schedule of Investments in Unrealized Loss Position (Details) - USD ($) $ in Thousands | Dec. 31, 2024 | Dec. 31, 2023
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Less than 12 months, fair value, available for sale securities | $ 43,189 | $ 58,754
Less than 12 months, unrealized loss, available for sale securities | (511) | (637)
12 months or longer, unrealized loss, fair value, available for sale securities | 160,221 | 209,362
12 months or longer, unrealized loss, available for sale securities | (29,057) | (36,064)
Available for sale securities, fair value, total | 203,410 | 268,116
Available for sale securities, unrealized losses total | (29,568) | (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 | 8,144 | 7,666
12 months or longer, unrealized loss, held to maturity securities | (356) | (834)
Held to maturity securities, fair value, total | 8,144 | 7,666
Held-to-maturity, total | (356) | (834)
Less than 12 months, fair value | 43,189 | 58,754
Less than 12 months, unrealized loss | (511) | (637)
12 months or longer, fair value | 168,365 | 217,028
12 months or longer, unrealized loss | (29,413) | (36,898)
Debt Securities, fair value, total | 211,554 | 275,782
Debt securities, unrealized loss, total | (29,924) | (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 | 15,093 | 15,972
12 months or longer, unrealized loss, available for sale securities | (3,154) | (3,179)
Available for sale securities, fair value, total | 15,093 | 15,972
Available for sale securities, unrealized losses total | (3,154) | (3,179)
Corporate Debt Securities [Member] |  |
Less than 12 months, fair value, available for sale securities | 6,781 | 959
Less than 12 months, unrealized loss, available for sale securities | (219) | (41)
12 months or longer, unrealized loss, fair value, available for sale securities | 5,337 | 4,300
12 months or longer, unrealized loss, available for sale securities | (663) | (700)
Available for sale securities, fair value, total | 12,118 | 5,259
Available for sale securities, unrealized losses total | (882) | (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 | 8,144 | 7,666
12 months or longer, unrealized loss, held to maturity securities | (356) | (834)
Held to maturity securities, fair value, total | 8,144 | 7,666
Held-to-maturity, total | (356) | (834)
Municipal Bonds [Member] |  |
Less than 12 months, fair value, available for sale securities | 1,677 | 3,922
Less than 12 months, unrealized loss, available for sale securities | (10) | (23)
12 months or longer, unrealized loss, fair value, available for sale securities | 68,667 | 113,577
12 months or longer, unrealized loss, available for sale securities | (12,420) | (19,375)
Available for sale securities, fair value, total | 70,344 | 117,499
Available for sale securities, unrealized losses total | (12,430) | (19,398)
Collateralized Mortgage-Backed Securities [Member] |  |
Less than 12 months, fair value, available for sale securities | 31,093 | 20,662
Less than 12 months, unrealized loss, available for sale securities | (241) | (113)
12 months or longer, unrealized loss, fair value, available for sale securities | 63,934 | 67,376
12 months or longer, unrealized loss, available for sale securities | (11,728) | (11,732)
Available for sale securities, fair value, total | 95,027 | 88,038
Available for sale securities, unrealized losses total | (11,969) | (11,845)
Asset-Backed Securities [Member] |  |
Less than 12 months, fair value, available for sale securities | 3,638 | 33,211
Less than 12 months, unrealized loss, available for sale securities | (41) | (460)
12 months or longer, unrealized loss, fair value, available for sale securities | 7,190 | 8,137
12 months or longer, unrealized loss, available for sale securities | (1,092) | (1,078)
Available for sale securities, fair value, total | 10,828 | 41,348
Available for sale securities, unrealized losses total | $ (1,133) | $ (1,538)

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