Investments In Securities and Fair Value (Schedule Of Gross Unrealized Gains And Losses And Amortized Cost For Securities) (Details) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)
Debt and Equity Securities, FV-NI [Line Items]
Impairment amount for cost-method investments	$ 0	$ 0
Total, amortized cost	66,209	75,511
Fixed maturity securities, available-for-sale, at fair value (amortized cost: March 31, 2022: $66,209; December 31, 2021: $75,511)	67,725	79,791
Other-than-temporary impairment loss, debt securities, available-for-sale, recognized in earnings	0
General obligations of U.S. states, territories and political subdivisions
Debt and Equity Securities, FV-NI [Line Items]
Debt securities, available-for-sale, accumulated gross unrealized gain, before tax	224	922
Debt securities, available-for-sale, accumulated gross unrealized loss, before tax	0	0
Total, amortized cost	15,011	16,669
Fixed maturity securities, available-for-sale, at fair value (amortized cost: March 31, 2022: $66,209; December 31, 2021: $75,511)	$ 15,235	$ 17,591
Special revenue issuer obligations of U.S. states, territories and political subdivisions
Debt and Equity Securities, FV-NI [Line Items]
Number of Special Revenue Bonds	45	45
Debt securities, available-for-sale, accumulated gross unrealized gain, before tax	$ 806	$ 2,453
Debt securities, available-for-sale, accumulated gross unrealized loss, before tax	56	2
Total, amortized cost	40,620	41,753
Fixed maturity securities, available-for-sale, at fair value (amortized cost: March 31, 2022: $66,209; December 31, 2021: $75,511)	41,370	44,204
Corporate debt securities
Debt and Equity Securities, FV-NI [Line Items]
Debt securities, available-for-sale, accumulated gross unrealized gain, before tax	707	955
Debt securities, available-for-sale, accumulated gross unrealized loss, before tax	165	48
Total, amortized cost	10,578	17,089
Fixed maturity securities, available-for-sale, at fair value (amortized cost: March 31, 2022: $66,209; December 31, 2021: $75,511)	11,120	17,996
Total fixed maturities
Debt and Equity Securities, FV-NI [Line Items]
Debt securities, available-for-sale, accumulated gross unrealized gain, before tax	1,737	4,330
Debt securities, available-for-sale, accumulated gross unrealized loss, before tax	221	50
Total, amortized cost	66,209	75,511
Fixed maturity securities, available-for-sale, at fair value (amortized cost: March 31, 2022: $66,209; December 31, 2021: $75,511)	$ 67,725	$ 79,791

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