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Note 2 - Investments - Schedule of Investments in Unrealized Loss Position (Details) - USD ($) $ in Thousands | Mar. 31, 2025 | Dec. 31, 2024
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Less than 12 months, fair value, available for sale securities | $ 39,888 | $ 43,189
Less than 12 months, unrealized loss, available for sale securities | (315) | (511)
12 months or longer, unrealized loss, fair value, available for sale securities | 165,154 | 160,221
12 months or longer, unrealized loss, available for sale securities | (26,869) | (29,057)
Available for sale securities, fair value, total | 205,042 | 203,410
Available for sale securities, unrealized losses total | (27,184) | (29,568)
Less than 12 months, fair value, held to maturity | 1,937 | 0
Less than 12 months, held to maturity securities | (63) | 0
12 months or longer, unrealized loss, fair value, held to maturity securities | 4,319 | 8,144
12 months or longer, unrealized loss, held to maturity securities | (180) | (356)
Held to maturity securities, fair value, total | 6,256 | 8,144
Held-to-maturity, total | (243) | (356)
Less than 12 months, fair value | 41,825 | 43,189
Less than 12 months, unrealized loss | (378) | (511)
12 months or longer, fair value | 169,473 | 168,365
12 months or longer, unrealized loss | (27,049) | (29,413)
Debt Securities, fair value, total | 211,298 | 211,554
Debt securities, unrealized loss, total | (27,427) | (29,924)
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 | 15,523 | 15,093
12 months or longer, unrealized loss, available for sale securities | (2,728) | (3,154)
Available for sale securities, fair value, total | 15,523 | 15,093
Available for sale securities, unrealized losses total | (2,728) | (3,154)
Corporate Debt Securities [Member] |  |
Less than 12 months, fair value, available for sale securities | 2,983 | 6,781
Less than 12 months, unrealized loss, available for sale securities | (17) | (219)
12 months or longer, unrealized loss, fair value, available for sale securities | 9,196 | 5,337
12 months or longer, unrealized loss, available for sale securities | (804) | (663)
Available for sale securities, fair value, total | 12,179 | 12,118
Available for sale securities, unrealized losses total | (821) | (882)
Less than 12 months, fair value, held to maturity | 1,937 | 0
Less than 12 months, held to maturity securities | (63) | 0
12 months or longer, unrealized loss, fair value, held to maturity securities | 4,319 | 8,144
12 months or longer, unrealized loss, held to maturity securities | (180) | (356)
Held to maturity securities, fair value, total | 6,256 | 8,144
Held-to-maturity, total | (243) | (356)
Municipal Bonds [Member] |  |
Less than 12 months, fair value, available for sale securities | 1,674 | 1,677
Less than 12 months, unrealized loss, available for sale securities | (4) | (10)
12 months or longer, unrealized loss, fair value, available for sale securities | 68,447 | 68,667
12 months or longer, unrealized loss, available for sale securities | (12,370) | (12,420)
Available for sale securities, fair value, total | 70,121 | 70,344
Available for sale securities, unrealized losses total | (12,374) | (12,430)
Collateralized Mortgage-Backed Securities [Member] |  |
Less than 12 months, fair value, available for sale securities | 35,231 | 31,093
Less than 12 months, unrealized loss, available for sale securities | (294) | (241)
12 months or longer, unrealized loss, fair value, available for sale securities | 65,190 | 63,934
12 months or longer, unrealized loss, available for sale securities | (10,008) | (11,728)
Available for sale securities, fair value, total | 100,421 | 95,027
Available for sale securities, unrealized losses total | (10,302) | (11,969)
Asset-Backed Securities [Member] |  |
Less than 12 months, fair value, available for sale securities | 0 | 3,638
Less than 12 months, unrealized loss, available for sale securities | 0 | (41)
12 months or longer, unrealized loss, fair value, available for sale securities | 6,798 | 7,190
12 months or longer, unrealized loss, available for sale securities | (959) | (1,092)
Available for sale securities, fair value, total | 6,798 | 10,828
Available for sale securities, unrealized losses total | $ (959) | $ (1,133)

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