Summary of Investments, Other than Investments in Related Parties: Summary Of Investments Other Than Investments In Related Parties Table Text Block (Details) $ in Thousands	Dec. 31, 2017 USD ($)
Summary of Investments, Other than Investments in Related Parties, Cost	$ 483,227
Summary of Investments, Other than Investments in Related Parties, Fair Value	476,898
Summary of Investments, Other than Investments in Related Parties, Carrying Amount	476,898
US Treasury and Government
Summary of Investments, Other than Investments in Related Parties, Cost	95,411
Summary of Investments, Other than Investments in Related Parties, Fair Value	94,810
Summary of Investments, Other than Investments in Related Parties, Carrying Amount	94,810
US States and Political Subdivisions Debt Securities
Summary of Investments, Other than Investments in Related Parties, Cost	182,664
Summary of Investments, Other than Investments in Related Parties, Fair Value	179,643
Summary of Investments, Other than Investments in Related Parties, Carrying Amount	179,643
Foreign Government Debt
Summary of Investments, Other than Investments in Related Parties, Cost	4,227
Summary of Investments, Other than Investments in Related Parties, Fair Value	4,150
Summary of Investments, Other than Investments in Related Parties, Carrying Amount	4,150
Public Utility, Bonds
Summary of Investments, Other than Investments in Related Parties, Cost	15,865
Summary of Investments, Other than Investments in Related Parties, Fair Value	15,717
Summary of Investments, Other than Investments in Related Parties, Carrying Amount	15,717
Other Corporate Bonds
Summary of Investments, Other than Investments in Related Parties, Cost	139,988
Summary of Investments, Other than Investments in Related Parties, Fair Value	137,407
Summary of Investments, Other than Investments in Related Parties, Carrying Amount	137,407
Mandatorily Redeemable Preferred Stock
Summary of Investments, Other than Investments in Related Parties, Cost	10,006
Summary of Investments, Other than Investments in Related Parties, Fair Value	10,185
Summary of Investments, Other than Investments in Related Parties, Carrying Amount	10,185
Fixed Maturities
Summary of Investments, Other than Investments in Related Parties, Cost	448,161
Summary of Investments, Other than Investments in Related Parties, Fair Value	441,912
Summary of Investments, Other than Investments in Related Parties, Carrying Amount	441,912
Industrial, Miscellaneous, and All Others
Summary of Investments, Other than Investments in Related Parties, Cost	2,612
Summary of Investments, Other than Investments in Related Parties, Fair Value	2,490
Summary of Investments, Other than Investments in Related Parties, Carrying Amount	2,490
Nonredeemable Preferred Stock
Summary of Investments, Other than Investments in Related Parties, Cost	3,588
Summary of Investments, Other than Investments in Related Parties, Fair Value	3,630
Summary of Investments, Other than Investments in Related Parties, Carrying Amount	3,630
Equity Securities
Summary of Investments, Other than Investments in Related Parties, Cost	6,200
Summary of Investments, Other than Investments in Related Parties, Fair Value	6,120
Summary of Investments, Other than Investments in Related Parties, Carrying Amount	6,120
Short-term Investments
Summary of Investments, Other than Investments in Related Parties, Cost	10,319
Summary of Investments, Other than Investments in Related Parties, Fair Value	10,319
Summary of Investments, Other than Investments in Related Parties, Carrying Amount	10,319
Other Long-term Investments
Summary of Investments, Other than Investments in Related Parties, Cost	18,547
Summary of Investments, Other than Investments in Related Parties, Fair Value	18,547
Summary of Investments, Other than Investments in Related Parties, Carrying Amount	$ 18,547

This element represents the carrying (reported) amount of the entity's investments as of the balance sheet date. This amount may represent the individual investment's or group of similar investments' original cost, fair value, or such other amount at which the investment is shown in the entity's balance sheet.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 946
-SubTopic 320
-Section S99
-Paragraph 7
-Subparagraph (SX 210.12-15)
-URI http://asc.fasb.org/extlink&oid=50485924&loc=d3e611379-123010

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This item represents the original cost of the entity's investments including investments in equity securities and, as to fixed maturities, original cost reduced by repayments and adjusted for amortization of premiums or accrual of discounts.

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This item represents the reported amount of the entity's investments measured at fair value. Fair value is the price that would be received to sell an investment in an orderly transaction between market participants at the balance sheet [measurement] date.

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