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3) Investments: Investments Classified by Contractual Maturity Date (Details) - USD ($) | Sep. 30, 2020 | Dec. 31, 2019
--- | --- | ---
Amortized Cost | $ 319,641,394 |
Held to maturity securities, Estimated fair value | 344,917,387 |
Due in 1 year |  |
Amortized Cost | 50,670,550 |
Held to maturity securities, Estimated fair value | 51,171,942 |
Due in 2-5 years |  |
Amortized Cost | 74,293,341 |
Held to maturity securities, Estimated fair value | 77,094,479 |
Due in 5-10 years |  |
Amortized Cost | 85,128,399 |
Held to maturity securities, Estimated fair value | 92,517,720 |
Due in more than 10 years |  |
Amortized Cost | 77,392,080 |
Held to maturity securities, Estimated fair value | 91,191,293 |
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises |  |
Amortized Cost | 31,887,810 | $ 31,475,280
Held to maturity securities, Estimated fair value | 32,701,709 | 31,832,498
Redeemable Preferred Stock |  |
Amortized Cost | 269,214 | 364,339
Held to maturity securities, Estimated fair value | $ 240,244 | $ 364,339

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