Investments, Debt Securities by Contractual Maturity (Details) - USD ($)	Mar. 31, 2020	Dec. 31, 2019
Amortized cost [Abstract]
Due in one year or less	$ 11,796,278
Due after one year through five years	58,507,802
Due after five years through ten years	46,860,963
Due after ten years	43,634,389
Original or amortized cost	160,799,432	$ 159,959,855
Fair value [Abstract]
Due in one year or less	12,089,426
Due after one year through five years	60,788,411
Due after five years through ten years	53,482,062
Due after ten years	47,343,537
Estimated fair value	$ 173,703,436	$ 171,629,373	[1]

[1] Balance sheet audited at December 31, 2018.