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Investments - Schedule of held to maturity securities by contractual maturity (Details) - USD ($) | Mar. 31, 2025 | Dec. 31, 2024
--- | --- | ---
Net Investment Income [Line Items] |  |
Cost or Amortized Cost | $ 7,046,023 | $ 7,047,342
Estimated Fair Value | 5,976,487 | 5,959,265
Less than one year |  |
Net Investment Income [Line Items] |  |
Cost or Amortized Cost | 499,859 | 499,719
Estimated Fair Value | 499,820 | 499,065
One to five years |  |
Net Investment Income [Line Items] |  |
Cost or Amortized Cost | 2,053,225 | 622,375
Estimated Fair Value | 1,949,757 | 600,288
Five to ten years |  |
Net Investment Income [Line Items] |  |
Cost or Amortized Cost | 0 | 1,427,579
Estimated Fair Value | 0 | 1,323,600
More than 10 years |  |
Net Investment Income [Line Items] |  |
Cost or Amortized Cost | 4,492,939 | 4,497,669
Estimated Fair Value | $ 3,526,910 | $ 3,536,312

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