v2.3.0.15

Investments (Narrative) (Details) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2011	Dec. 31, 2010
Schedule of Available-for-sale Securities [Line Items]
Available for sale securities in unrealized loss position, number of positions	105	363
Available-for-sale securities, Estimated Fair Value	$ 391,247	$ 1,215,371
Available-for-sale securities, Gross Unrealized Holding and Other-Than-Temporary Impairment Losses	(35,124)	(56,205)
Number of available-for-sale securities positions in a continuous unrealized loss position for greater than one year at period end	31
Available-for-sale securities, Estimated Fair Value, 12 months or longer	65,721	53,923
Available-for-sale securities, Gross Unrealized Holding and Other-Than-Temporary Impairment Losses, 12 months or longer	(3,989)	(5,315)
Fixed Maturities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, Estimated Fair Value	114,828	1,175,909
Available-for-sale securities, Gross Unrealized Holding and Other-Than-Temporary Impairment Losses	(16,360)	(54,010)
Number of available-for-sale securities positions in a continuous unrealized loss position for greater than one year at period end	30	19
Available-for-sale securities, Estimated Fair Value, 12 months or longer	53,438	53,923
Available-for-sale securities, Gross Unrealized Holding and Other-Than-Temporary Impairment Losses, 12 months or longer	(2,867)	(5,315)
Equity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale securities, Estimated Fair Value	186,420	39,462
Available-for-sale securities, Gross Unrealized Holding and Other-Than-Temporary Impairment Losses	(18,763)	(2,195)
Number of available-for-sale securities positions in a continuous unrealized loss position for greater than one year at period end	1
Available-for-sale securities, Estimated Fair Value, 12 months or longer	12,283	0
Available-for-sale securities, Gross Unrealized Holding and Other-Than-Temporary Impairment Losses, 12 months or longer	$ (1,122)	$ 0

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