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Investments (OTTI by Asset Type) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
OTTI Losses Gross	$ 1,711	$ 11,998	$ 16,225
Other-than-temporary impairments on fixed maturity securities recognized in other comprehensive income	(2,553)	(1,188)	(1,433)
Total OTTI charges recognized in earnings	4,264	13,186	17,658
Fixed Maturity Securities [Member]
OTTI Losses Gross	(1,462)	633	13,682
Other-than-temporary impairments on fixed maturity securities recognized in other comprehensive income	(2,553)	(1,188)	(1,433)
Total OTTI charges recognized in earnings	1,091	1,821	15,115
Equity Securities [Member]
OTTI Losses Gross	3,173	11,365	2,543
Other-than-temporary impairments on fixed maturity securities recognized in other comprehensive income	0	0	0
Total OTTI charges recognized in earnings	3,173	11,365	2,543
Fixed Maturity Securities [Member] | Obligations of States and Political Subdivisions [Member]
OTTI Losses Gross		17	197
Other-than-temporary impairments on fixed maturity securities recognized in other comprehensive income		0	0
Total OTTI charges recognized in earnings		17	197
Fixed Maturity Securities [Member] | Corporate Securities [Member]
OTTI Losses Gross		244
Other-than-temporary impairments on fixed maturity securities recognized in other comprehensive income		0
Total OTTI charges recognized in earnings		244
Fixed Maturity Securities [Member] | Asset-backed Securities [Member]
OTTI Losses Gross	98	175	(20)
Other-than-temporary impairments on fixed maturity securities recognized in other comprehensive income	0	(546)	(179)
Total OTTI charges recognized in earnings	98	721	159
Fixed Maturity Securities [Member] | Commercial Mortgage Backed Securities [Member]
OTTI Losses Gross	(1,525)	(149)	5,552
Other-than-temporary impairments on fixed maturity securities recognized in other comprehensive income	(2,335)	(843)	(863)
Total OTTI charges recognized in earnings	810	694	6,415
Average unrealized unrecognized loss as compared to amortized cost percentage			60.00%
Fixed Maturity Securities [Member] | Residential Mortgage Backed Securities [Member]
OTTI Losses Gross	(35)	346	7,953
Other-than-temporary impairments on fixed maturity securities recognized in other comprehensive income	(218)	201	(391)
Total OTTI charges recognized in earnings	183	145	8,344
Number of impairments due to intent to sell			2
Securities Which Will Not Recover In The Near Term [Member] | Equity Securities [Member]
Total OTTI charges recognized in earnings	1,000	8,500
Securities In Loss Position With Intent to Sell [Member] | Equity Securities [Member]
Total OTTI charges recognized in earnings	$ 2,200	$ 2,900

X

- Definition

The average unrealized/unrecognized loss in comparison to the securities' amortized cost.

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- Definition

This item represents the number of investments which made up the impairment losses for debt and equity securities recognized in earnings for the reporting periods due to the Company's intent to sell.

+ References

No definition available.

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- Definition

The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

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- Definition

Before tax amount of other than temporary impairment (OTTI) on a debt security, categorized as either available-for-sale or held-to-maturity, recognized in other comprehensive income (loss).

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- Definition

The amount of other than temporary impairment (OTTI) losses on equity securities, OTTI related to credit losses on debt securities, and OTTI losses on debt securities when the entity intends to sell the securities or it is more likely than not that the entity will be required to sell the securities before recovery of its amortized cost basis. Additionally, this item includes OTTI losses recognized during the period on investments accounted for under the cost method of accounting.

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