3) Investments: Investments Classified by Contractual Maturity Date (Details) - USD ($)	Mar. 31, 2020	Dec. 31, 2019
Amortized Cost	$ 323,056,426	$ 323,056,426
Held to maturity securities, Estimated fair value	329,145,562	329,145,562
Due in 1 year
Amortized Cost	73,238,213
Held to maturity securities, Estimated fair value	73,502,130
Due in 2-5 years
Amortized Cost	71,857,335
Held to maturity securities, Estimated fair value	73,583,452
Due in 5-10 years
Amortized Cost	77,612,911
Held to maturity securities, Estimated fair value	76,748,155
Due in more than 10 years
Amortized Cost	68,194,390
Held to maturity securities, Estimated fair value	73,831,361
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises
Amortized Cost	31,789,238	31,475,280
Held to maturity securities, Estimated fair value	31,106,494	31,832,498
Redeemable Preferred Stock
Amortized Cost	364,339	364,339
Held to maturity securities, Estimated fair value	$ 373,970	$ 364,339