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, 2022 USD ($)	Dec. 31, 2021 USD ($)
Debt and Equity Securities, FV-NI [Line Items]
Total, amortized cost	$ 53,775	$ 75,511
Fixed maturity securities, available-for-sale, at fair value	53,989	79,791
Government obligations
Debt and Equity Securities, FV-NI [Line Items]
Total, amortized cost	4,329	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	0	0
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	7	0
Fixed maturity securities, available-for-sale, at fair value	4,322	0
General obligations of U.S. states, territories and political subdivisions
Debt and Equity Securities, FV-NI [Line Items]
Total, amortized cost	8,561	16,669
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	21	922
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	36	0
Fixed maturity securities, available-for-sale, at fair value	8,546	17,591
Special revenue issuer obligations of U.S. states, territories and political subdivisions
Debt and Equity Securities, FV-NI [Line Items]
Total, amortized cost	30,123	41,753
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	106	2,453
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	219	2
Fixed maturity securities, available-for-sale, at fair value	$ 30,010	$ 44,204
Number of Special Revenue Bonds	40	40
Corporate debt securities
Debt and Equity Securities, FV-NI [Line Items]
Total, amortized cost	$ 10,762	$ 17,089
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	417	955
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	68	48
Fixed maturity securities, available-for-sale, at fair value	11,111	17,996
Total fixed maturity securities
Debt and Equity Securities, FV-NI [Line Items]
Total, amortized cost	53,775	75,511
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Gain, before Tax	544	4,330
Debt Securities, Available-for-sale, Accumulated Gross Unrealized Loss, before Tax	330	50
Fixed maturity securities, available-for-sale, at fair value	$ 53,989	$ 79,791

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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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