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, 2020 USD ($)	Dec. 31, 2019 USD ($)
Government obligations
Debt and Equity Securities, FV-NI [Line Items]
Fixed maturities, available-for-sale, amortized cost	$ 24,026	$ 25,161
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax	57	6
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	0	4
Available-for-sale, at fair value, Estimated Fair Value	24,083	25,163
General obligations of U.S. states, territories and political subdivisions
Debt and Equity Securities, FV-NI [Line Items]
Fixed maturities, available-for-sale, amortized cost	17,391	18,887
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax	1,262	843
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	0	0
Available-for-sale, at fair value, Estimated Fair Value	18,653	19,730
Special revenue issuer obligations of U.S. states, territories and political subdivisions
Debt and Equity Securities, FV-NI [Line Items]
Fixed maturities, available-for-sale, amortized cost	44,939	51,188
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax	3,270	2,530
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	3	20
Available-for-sale, at fair value, Estimated Fair Value	$ 48,206	$ 53,698
Number of Special Revenue Bonds	50	50
Corporate debt securities
Debt and Equity Securities, FV-NI [Line Items]
Fixed maturities, available-for-sale, amortized cost	$ 25,681	$ 5,431
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax	1,114	621
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	24	5
Available-for-sale, at fair value, Estimated Fair Value	26,771	6,047
Total fixed maturity securities
Debt and Equity Securities, FV-NI [Line Items]
Fixed maturities, available-for-sale, amortized cost	112,037	100,667
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax	5,703	4,000
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	27	29
Available-for-sale, at fair value, Estimated Fair Value	$ 117,713	$ 104,638

Number of Special Revenue Bonds

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- Definition

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

+ References

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- Definition

Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=121645371&loc=d3e27161-111563

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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

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This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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+ References

No definition available.

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