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Investments - Schedule of held-to-maturity securities (Details) - USD ($) | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2025 | Dec. 31, 2024
Net Investment Income [Line Items] |  |
Cost or Amortized Cost | $ 7,046,023 | $ 7,047,342
Gross Unrealized Gains | 381 | 0
Gross unrealized losses - less than 12 months | (17,142) | (40,284)
Gross unrealized loss - more than 12 months | (1,052,775) | (1,047,793)
Estimated Fair Value | 5,976,487 | 5,959,265
Net Unrealized Gains/ (Losses) | (1,069,536) | (1,088,077)
U.S. Treasury securities |  |
Net Investment Income [Line Items] |  |
Cost or Amortized Cost | 1,229,249 | 1,229,170
Gross Unrealized Gains | 381 | 0
Gross unrealized losses - less than 12 months | (17,103) | (39,630)
Gross unrealized loss - more than 12 months | (10,865) | (15,990)
Estimated Fair Value | 1,201,662 | 1,173,550
Net Unrealized Gains/ (Losses) | (27,587) | (55,620)
Political subdivisions of States, Territories and Possessions |  |
Net Investment Income [Line Items] |  |
Cost or Amortized Cost | 499,859 | 499,719
Gross Unrealized Gains | 0 | 0
Gross unrealized losses - less than 12 months | (39) | (654)
Gross unrealized loss - more than 12 months | 0 | 0
Estimated Fair Value | 499,820 | 499,065
Net Unrealized Gains/ (Losses) | (39) | (654)
Exchange traded debt |  |
Net Investment Income [Line Items] |  |
Cost or Amortized Cost | 304,111 | 304,111
Gross Unrealized Gains | 0 | 0
Gross unrealized losses - less than 12 months | 0 | 0
Gross unrealized loss - more than 12 months | (60,111) | (55,611)
Estimated Fair Value | 244,000 | 248,500
Net Unrealized Gains/ (Losses) | (60,111) | (55,611)
Corporate and other bonds industrial and miscellaneous |  |
Net Investment Income [Line Items] |  |
Cost or Amortized Cost | 5,012,804 | 5,014,342
Gross Unrealized Gains | 0 | 0
Gross unrealized losses - less than 12 months | 0 | 0
Gross unrealized loss - more than 12 months | (981,799) | (976,192)
Estimated Fair Value | 4,031,005 | 4,038,150
Net Unrealized Gains/ (Losses) | $ (981,799) | $ (976,192)

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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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