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Investments (OTTI by Asset Type) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
OTTI Losses Gross	$ 11,998	$ 16,225	$ 64,184
Other-than-temporary impairments on fixed maturity securities recognized in other comprehensive income	(1,188)	(1,433)	8,768
OTTI Losses Recognized in Earnings	13,186	17,658	55,416
Equity Securities [Member]
OTTI Losses Gross	11,365	2,543	2,107
Other-than-temporary impairments on fixed maturity securities recognized in other comprehensive income	0	0	0
OTTI Losses Recognized in Earnings	11,365	2,543	2,107
Residential Mortgage Backed Securities ("RMBS") [Member]
Number of Impairments due to intent to sell		2
Fixed Maturity Securities [Member]
OTTI Losses Gross	633	13,682	62,077
Other-than-temporary impairments on fixed maturity securities recognized in other comprehensive income	(1,188)	(1,433)	8,768
OTTI Losses Recognized in Earnings	1,821	15,115	53,309
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
OTTI Losses Recognized in Earnings	17	197
Fixed Maturity Securities [Member] | Corporate Securities [Member]
OTTI Losses Gross	244		1,271
Other-than-temporary impairments on fixed maturity securities recognized in other comprehensive income	0		0
OTTI Losses Recognized in Earnings	244		1,271
Fixed Maturity Securities [Member] | Asset-backed Securities ("ABS") [Member]
OTTI Losses Gross	175	(20)	1,190
Other-than-temporary impairments on fixed maturity securities recognized in other comprehensive income	(546)	(179)	(1,292)
OTTI Losses Recognized in Earnings	721	159	2,482
Fixed Maturity Securities [Member] | Commercial Mortgage-backed Securities ("CMBS") [Member]
OTTI Losses Gross	(149)	5,552	18,865
Other-than-temporary impairments on fixed maturity securities recognized in other comprehensive income	(843)	(863)	7,088
OTTI Losses Recognized in Earnings	694	6,415	11,777
Average unrealized unrecognized loss as compared to amortized cost percentage		60.00%
Decline In Fair Value As Compared To Amortized Cost			77.00%
Conditional Default Rates Range Low End Of Range			2.5
Conditional Default Rates Range High End Of Range			3.0
Fixed Maturity Securities [Member] | Residential Mortgage Backed Securities ("RMBS") [Member]
OTTI Losses Gross	346	7,953	40,751
Other-than-temporary impairments on fixed maturity securities recognized in other comprehensive income	201	(391)	2,972
OTTI Losses Recognized in Earnings	145	8,344	37,779
Decline In Fair Value As Compared To Amortized Cost			65.00%
Conditional Default Rates			0.33
Securities In Loss Position With Intent to Sell [Member] | Equity Securities [Member]
OTTI Losses Recognized in Earnings	2,900
Securities Which Will Not Recover In The Near Term [Member] | Equity Securities [Member]
OTTI Losses Recognized in Earnings	$ 8,500

X

- Definition

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

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Proportion of all loans outstanding in a pool at the beginning of a time period that are expected to default during that period.

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The high range of the proportion of all loans outstanding in a pool at the beginning of a time period that are expected to default during that period.

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- Definition

The low range of the proportion of all loans outstanding in a pool at the beginning of a time period that are expected to default during that period.

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- Definition

The decline in fair value in comparison to the securities' amortized cost.

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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.

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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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The amount of other than temporary impairment (OTTI) loss on a debt security, categorized as either Available-for-sale or Held-to-maturity, related to factors other than credit losses when the entity does not intend to sell the security and it is not more likely than not that the entity will be required to sell the security before recovery of its amortized cost basis. This amount, which includes the portion attributable to the noncontrolling interest, if any, is deducted from the total impairment losses of investments (before taxes) presented on the income statement; this amount is also referred to as the amount incurred by the reporting entity or the consolidated entity.

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