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Investments - Schedule of securities with unrealized losses (Details) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2025 USD ($) position | Dec. 31, 2024 USD ($) position
U.S. Treasury securities and obligations of U.S. government corporations and agencies |  |
Net Investment Income [Line Items] |  |
Estimated fair value - less than 12 months | $ 0 | $ 0
Unrealized losses - less than 12 months | $ 0 | $ 0
Number of positions held - less than 12 months | position | 0 | 0
Estimated fair value - 12 months or more | $ 0 | $ 0
Unrealized losses - 12 months or more | $ 0 | $ 0
Number of positions held - 12 months or more | position | 0 | 0
Estimated fair value - total | $ 0 | $ 0
Unrealized losses - total | 0 | 0
Political subdivisions of States, Territories and Possessions |  |
Net Investment Income [Line Items] |  |
Estimated fair value - less than 12 months | 0 | 7,705,370
Unrealized losses - less than 12 months | $ 0 | $ (73,589)
Number of positions held - less than 12 months | position | 0 | 6
Estimated fair value - 12 months or more | $ 13,539,593 | $ 13,167,726
Unrealized losses - 12 months or more | $ (2,945,087) | $ (3,324,491)
Number of positions held - 12 months or more | position | 12 | 12
Estimated fair value - total | $ 13,539,593 | $ 20,873,096
Unrealized losses - total | (2,945,087) | (3,398,080)
Corporate and other bonds industrial and miscellaneous |  |
Net Investment Income [Line Items] |  |
Estimated fair value - less than 12 months | 51,949,158 | 51,411,296
Unrealized losses - less than 12 months | $ (495,587) | $ (1,024,461)
Number of positions held - less than 12 months | position | 60 | 60
Estimated fair value - 12 months or more | $ 51,520,947 | $ 55,381,083
Unrealized losses - 12 months or more | $ (3,992,684) | $ (4,690,597)
Number of positions held - 12 months or more | position | 63 | 68
Estimated fair value - total | $ 103,470,105 | $ 106,792,379
Unrealized losses - total | (4,488,271) | (5,715,058)
Residential mortgage and other asset backed securities |  |
Net Investment Income [Line Items] |  |
Estimated fair value - less than 12 months | 5,884,488 | 19,315,521
Unrealized losses - less than 12 months | $ (17,773) | $ (209,890)
Number of positions held - less than 12 months | position | 8 | 22
Estimated fair value - 12 months or more | $ 35,096,038 | $ 35,206,442
Unrealized losses - 12 months or more | $ (5,533,927) | $ (6,211,339)
Number of positions held - 12 months or more | position | 36 | 36
Estimated fair value - total | $ 40,980,526 | $ 54,521,963
Unrealized losses - total | (5,551,700) | (6,421,229)
Total fixed-maturity securities |  |
Net Investment Income [Line Items] |  |
Estimated fair value - less than 12 months | 57,833,646 | 78,432,187
Unrealized losses - less than 12 months | $ (513,360) | $ (1,307,940)
Number of positions held - less than 12 months | position | 68 | 88
Estimated fair value - 12 months or more | $ 100,156,578 | $ 103,755,251
Unrealized losses - 12 months or more | $ (12,471,698) | $ (14,226,427)
Number of positions held - 12 months or more | position | 111 | 116
Estimated fair value - total | $ 157,990,224 | $ 182,187,438
Unrealized losses - total | $ (12,985,058) | $ (15,534,367)

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 944 -SubTopic 220 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-04(2)(a)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147477250/944-220-S99-1 + Details
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