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Investments - Schedule of held to maturity securities by contractual maturity (Details) - USD ($) | Sep. 30, 2024 | Dec. 31, 2023
--- | --- | ---
Net Investment Income [Line Items] |  |
Cost or Amortized Cost | $ 7,048,662 | $ 7,052,541
Estimated Fair Value | 6,278,968 | 6,106,148
Less than one year |  |
Net Investment Income [Line Items] |  |
Cost or Amortized Cost | 499,581 | 0
Estimated Fair Value | 499,850 | 0
One to five years |  |
Net Investment Income [Line Items] |  |
Cost or Amortized Cost | 622,309 | 1,121,288
Estimated Fair Value | 608,231 | 1,097,101
Five to ten years |  |
Net Investment Income [Line Items] |  |
Cost or Amortized Cost | 1,424,371 | 1,414,911
Estimated Fair Value | 1,350,945 | 1,270,770
More than 10 years |  |
Net Investment Income [Line Items] |  |
Cost or Amortized Cost | 4,502,401 | 4,516,342
Estimated Fair Value | $ 3,819,942 | $ 3,738,277

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