3) Investments: Investments Classified by Contractual Maturity Date (Details) - USD ($)	Mar. 31, 2019	Dec. 31, 2018
AmortizedCost	$ 231,378,413
Held to maturity securities, Estimated fair value	240,058,373
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises
AmortizedCost	15,637,703	$ 15,358,746
Held to maturity securities, Estimated fair value	15,868,835	15,277,280
Redeemable Preferred Stock
AmortizedCost	103,197	103,197
Held to maturity securities, Estimated fair value	107,069	$ 99,975
Due in 2017
AmortizedCost	16,752,164
Held to maturity securities, Estimated fair value	16,817,929
Due in 2018 Through 2021
AmortizedCost	66,507,390
Held to maturity securities, Estimated fair value	67,272,309
Due in 2022 Through 2026
AmortizedCost	66,149,179
Held to maturity securities, Estimated fair value	67,744,587
Due After 2026
AmortizedCost	66,228,780
Held to maturity securities, Estimated fair value	$ 72,247,644