Summary of Significant Accounting and Reporting Policies (Fixed Income Securities Contractual Maturity) (Details) - USD ($)	Dec. 31, 2018	Dec. 31, 2017
Debt Securities, Available-for-sale [Line Items]
Total	$ 520,567,359	$ 776,854,969
Fixed Income Securities [Member]
Debt Securities, Available-for-sale [Line Items]
Due within one year	166,443,311
Due between one and five years	113,806,135
Due over five years	21,072,946
Total	$ 301,322,392

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