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, 2018 USD ($)	Dec. 31, 2017 USD ($)
Government obligations
Debt and Equity Securities, FV-NI [Line Items]
Fixed maturities, available-for-sale, amortized cost	$ 1,023	$ 1,043
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax	0	0
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	7	1
Available-for-sale, at fair value, Estimated Fair Value	1,016	1,042
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	19,518	24,189
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax	229	505
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	143	50
Available-for-sale, at fair value, Estimated Fair Value	19,604	24,644
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	56,675	62,592
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax	1,237	2,218
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	329	165
Available-for-sale, at fair value, Estimated Fair Value	$ 57,583	$ 64,645
Number of Special Revenue Bonds	60	60
Corporate debt securities
Debt and Equity Securities, FV-NI [Line Items]
Fixed maturities, available-for-sale, amortized cost	$ 10,498	$ 12,490
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax	303	527
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	47	7
Available-for-sale, at fair value, Estimated Fair Value	10,754	13,010
Total fixed maturity securities
Debt and Equity Securities, FV-NI [Line Items]
Fixed maturities, available-for-sale, amortized cost	87,714	100,314
Available-for-sale Securities, Accumulated Gross Unrealized Gain, before Tax	1,769	3,250
Available-for-sale Securities, Accumulated Gross Unrealized Loss, before Tax	526	223
Available-for-sale, at fair value, Estimated Fair Value	$ 88,957	$ 103,341

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

No definition available.

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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=82897076&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

No definition available.

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- Definition

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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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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