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Summary Of Investments Other Than Investments In Related Parties (Details) - USD ($) $ in Thousands | Dec. 31, 2015 | Dec. 31, 2014
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Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |  |
Cost | $ 3,303,156 | $ 3,264,525
Fair value | 3,380,642 | 3,403,822
Amounts in the balance sheet | 3,380,642 | 3,403,822
Fixed Maturity Securities [Member] |  |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |  |
Cost | 2,804,275 | 2,503,494
Fair value | 2,880,003 | 2,618,400
Amounts in the balance sheet | 2,880,003 | 2,618,400
Fixed Maturity Securities [Member] | U.S. Government Bonds And Agencies [Member] |  |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |  |
Cost | 22,542 | 16,028
Fair value | 22,507 | 16,108
Amounts in the balance sheet | 22,507 | 16,108
Fixed Maturity Securities [Member] | Municipal Securities [Member] |  |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |  |
Cost | 2,417,046 | 2,160,710
Fair value | 2,505,039 | 2,275,455
Amounts in the balance sheet | 2,505,039 | 2,275,455
Fixed Maturity Securities [Member] | Collateralized Mortgage Backed Securities [Member] |  |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |  |
Cost | 49,639 | 45,519
Fair value | 49,839 | 47,691
Amounts in the balance sheet | 49,839 | 47,691
Fixed Maturity Securities [Member] | Corporate Debt Securities [Member] |  |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |  |
Cost | 255,606 | 258,940
Fair value | 243,372 | 256,930
Amounts in the balance sheet | 243,372 | 256,930
Fixed Maturity Securities [Member] | Collateralized Debt Obligations [Member] |  |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |  |
Cost | 50,710 | 22,297
Fair value | 50,548 | 22,216
Amounts in the balance sheet | 50,548 | 22,216
Fixed Maturity Securities [Member] | Collateralized Auto Loans [Member] |  |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |  |
Cost | 8,732 |
Fair value | 8,698 |
Amounts in the balance sheet | 8,698 |
Equity Securities [Member] |  |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |  |
Cost | 313,528 | 387,851
Fair value | 315,362 | 412,880
Amounts in the balance sheet | 315,362 | 412,880
Equity Securities [Member] | Common Stock [Member] |  |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |  |
Cost | 275,479 | 349,839
Fair value | 280,263 | 372,598
Amounts in the balance sheet | 280,263 | 372,598
Equity Securities [Member] | Non-Redeemable Preferred Stock [Member] |  |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |  |
Cost | 25,161 | 28,012
Fair value | 24,668 | 28,563
Amounts in the balance sheet | 24,668 | 28,563
Equity Securities [Member] | Partnership Interest in a Private Credit Fund [Member] |  |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |  |
Cost | 12,888 | 10,000
Fair value | 10,431 | 11,719
Amounts in the balance sheet | 10,431 | 11,719
Short-term Investments [Member] |  |
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items] |  |
Cost | 185,353 | 373,180
Fair value | 185,277 | 372,542
Amounts in the balance sheet | $ 185,277 | $ 372,542

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- Definition 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. + References 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 + Details
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- Definition 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. + References 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 + Details
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