Segment Information (Income From Continuing Operations, Before Federal Income Tax) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Underwriting loss, before federal income tax	$ (32,682)	$ (3,161)	$ (43,766)	$ (17,766)
GAAP combined ratio	109.20%	100.90%	106.20%	102.50%
Statutory combined ratio	109.50%	101.00%	106.10%	101.90%
Net investment income	39,345	36,545	82,818	71,251
Net realized gain (loss) on investments	2,146	(3,264)	7,906	(3,328)
Total investment income, before federal income tax	41,491	33,281	90,724	67,923
Total all segments	8,809	30,120	46,958	50,157
Interest expense	(4,559)	(4,655)	(9,116)	(9,497)
General corporate and other expenses	(3,029)	(2,617)	(8,849)	(10,165)
Income from continuing operations, before federal income tax	1,221	22,848	28,993	30,495
Total Commercial Lines [Member]
Underwriting loss, before federal income tax	(22,331)	3,305	(27,165)	(7,667)
Total Personal Lines [Member]
Underwriting loss, before federal income tax	$ (10,351)	$ (6,466)	$ (16,601)	$ (10,099)

The GAAP combined ratio (expressed as a percentage) is a calculation wherein the sum of: (i) loss and loss adjustment expenses (ii) underwriting expenses and (iii) dividends to policyholders is divided by net premiums earned.

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- Definition

Represents other corporate and general expenses that are not related to the entity's reportable segments.

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- Definition

Income or loss from continuing operations before income taxes, but includes income (loss) from equity method investments.

+ Details

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- Definition

The income earned from investments in securities and other investments including dividends, interest, and returns on other investments. This item does not include realized gains (losses).

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- Definition

The statutory combined ratio (expressed as a percentage) is the sum of: (i) the loss and loss expense ratio; (ii) the underwriting ratio; and (iii) the dividend ratio. The loss and loss expense ratio as well as the dividend ratio is calculated by dividing loss and loss expenses, as well as dividends to policyholders, by net premiums earned. The underwriting expense ratio is calculated by dividing underwriting expenses by net premiums written.

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The income earned from investments in securities and other investments including dividends, interest, and returns on other investments, including realized gains/losses.

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- Definition

Total of all reportable segments' income or loss from continuing operations, before federal income taxes.

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- Definition

Net premiums earned and other insurance income less net loss and loss expenses incurred, loss adjustment expenses, policy acquisition costs and other underwriting expenses.

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- Definition

Represents the portion of interest incurred in the period on debt arrangements that was charged against earnings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 03
-Paragraph 8
-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 34
-Paragraph 21

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- Definition

The net realized gains or losses on investments during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 04
-Paragraph 3
-Subparagraph a
-Article 7

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