SCHEDULE I -SUMMARY OF INVESTMENTS-OTHER THAN INVESTMENTS IN RELATED PARTIES (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Amount at which shown in the balance sheet	$ 15,430
Money markets fund classified with cash and cash equivalent and excluded from other investments in related party	59,309
Total Investments [Member]
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Cost	618,359
Fair value	698,112
Amount at which shown in the balance sheet	698,112	[1]
Limited Partnership [Member]
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Cost	81,230
Fair value	81,230
Amount at which shown in the balance sheet	81,230	[1]
Bonds [Member] | Total Fixed Maturities [Member]
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Cost	455,385
Fair value	451,809
Amount at which shown in the balance sheet	451,809	[1]
Bonds [Member] | U.S Government Obligations [Member]
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Cost	101,058
Fair value	101,094
Amount at which shown in the balance sheet	101,094	[1]
Bonds [Member] | Mortgage-backed Securities [Member]
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Cost	42,040
Fair value	42,506
Amount at which shown in the balance sheet	42,506	[1]
Bonds [Member] | State and Municipal Obligations [Member]
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Cost	113,133
Fair value	113,777
Amount at which shown in the balance sheet	113,777	[1]
Bonds [Member] | Foreign Government Obligations [Member]
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Cost	28,332
Fair value	27,466
Amount at which shown in the balance sheet	27,466	[1]
Bonds [Member] | Corporate Securities [Member]
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Cost	170,822
Fair value	166,966
Amount at which shown in the balance sheet	166,966	[1]
Common Stocks [Member] | Total Equity Securities [Member]
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Cost	78,778
Fair value	162,107
Amount at which shown in the balance sheet	162,107	[1]
Common Stocks [Member] | Industrial, Miscellaneous, and All Others [Member]
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Cost	78,778
Fair value	162,107
Amount at which shown in the balance sheet	162,107	[1]
Short-term [Member] | Total Short-term and Other [Member]
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Cost	2,966
Fair value	2,966
Amount at which shown in the balance sheet	2,966	[1]
Short-term [Member] | Certificates of Deposit [Member]
Summary of Investments, Other than Investments in Related Parties, Reportable Data [Line Items]
Cost	2,966
Fair value	2,966
Amount at which shown in the balance sheet	$ 2,966	[1]

[1] Investments presented above do not include $59,309 of money market funds classified with cash and cash equivalents in the balance sheet.