Investments in Securities and Fair Value Investments in Securities (Schedule of Gross Unrealized Gains and Losses and Amortized Cost for Securities) (Details) $ in Thousands	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Debt and Equity Securities, FV-NI [Line Items]
Total, amortized cost	$ 75,511	$ 112,037
Fixed maturity securities, available-for-sale, at fair value	79,791	117,713
Government obligations
Debt and Equity Securities, FV-NI [Line Items]
Total, amortized cost	0	24,026
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	0	57
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	0	0
Fixed maturity securities, available-for-sale, at fair value	0	24,083
General obligations of U.S. states, territories and political subdivisions
Debt and Equity Securities, FV-NI [Line Items]
Total, amortized cost	16,669	17,391
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	922	1,262
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	0	0
Fixed maturity securities, available-for-sale, at fair value	17,591	18,653
Special revenue issuer obligations of U.S. states, territories and political subdivisions
Debt and Equity Securities, FV-NI [Line Items]
Total, amortized cost	41,753	44,939
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	2,453	3,270
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	2	3
Fixed maturity securities, available-for-sale, at fair value	$ 44,204	$ 48,206
Number of Special Revenue Bonds	50	50
Corporate debt securities
Debt and Equity Securities, FV-NI [Line Items]
Total, amortized cost	$ 17,089	$ 25,681
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	955	1,114
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	48	24
Fixed maturity securities, available-for-sale, at fair value	17,996	26,771
Total fixed maturity securities
Debt and Equity Securities, FV-NI [Line Items]
Total, amortized cost	75,511	112,037
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	4,330	5,703
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	50	27
Fixed maturity securities, available-for-sale, at fair value	$ 79,791	$ 117,713

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Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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