Investments (Details 2) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Fixed maturity securities:
Amortized cost	$ 765,359	$ 761,441
Gross unrealized gains	65,034	56,077
Gross unrealized losses	(816)	(1,519)
Estimated fair value	829,577	815,999
U.S. Treasury securities and obligations of U.S. Government corporations and agencies [Member]
Fixed maturity securities:
Amortized cost	53,591	58,814
Gross unrealized gains	2,961	4,315
Gross unrealized losses	(11)	(39)
Estimated fair value	56,541	63,090
States of the U.S. and political subdivisions of the states [Member]
Fixed maturity securities:
Amortized cost	40,100	27,676
Gross unrealized gains	6,064	4,581
Estimated fair value	46,164	32,257
Corporate securities [Member]
Fixed maturity securities:
Amortized cost	304,725	298,452
Gross unrealized gains	36,089	29,601
Gross unrealized losses	(85)	(1,127)
Estimated fair value	340,729	326,926
Mortgage-backed securities [Member]
Fixed maturity securities:
Amortized cost	237,653	257,864
Gross unrealized gains	11,088	12,973
Gross unrealized losses	(501)	(26)
Estimated fair value	248,240	270,811
Commercial mortgage-backed securities [Member]
Fixed maturity securities:
Amortized cost	57,521	60,198
Gross unrealized gains	5,694	3,941
Gross unrealized losses		(178)
Estimated fair value	63,215	63,961
Asset-backed securities [Member]
Fixed maturity securities:
Amortized cost	71,769	58,437
Gross unrealized gains	3,138	666
Gross unrealized losses	(219)	(149)
Estimated fair value	74,688	58,954
Common stock [Member]
Fixed maturity securities:
Amortized cost	9,004	6,926
Gross unrealized gains	6
Gross unrealized losses	(234)	(175)
Estimated fair value	8,776	6,751
Preferred stock [Member]
Fixed maturity securities:
Amortized cost	2,789	2,789
Gross unrealized gains	317	212
Gross unrealized losses	(25)	(69)
Estimated fair value	$ 3,081	$ 2,932

Amount of debt securities categorized neither as held-to-maturity nor trading.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name FASB Staff Position (FSP)

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-Paragraph 15C

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 12

-Subparagraph b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 137

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 16

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

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-Section 50

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Reference 6: http://www.xbrl.org/2003/role/presentationRef

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Reference 7: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

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Reference 8: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 133

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 9: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 115

-Paragraph 13

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 10: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name FASB Staff Position (FSP)

-Number FAS115-1/124-1

-Paragraph 15D

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

+ Details

- Definition

This item represents the gross unrealized gains for securities, at a point in time, which are categorized neither as held-to-maturity nor trading securities.

+ References+ Details