Investments (Details 4) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
	Jun. 30, 2012	Jun. 30, 2012
Reconciliation Of Credit Losses Recognized In Earnings On Fixed Maturity Securities Held By The Company
Credit losses on securities held at beginning of the period in accumulated other comprehensive income	$ 13,715	$ 13,559
Additions for credit losses not previously recognized in other-than- temporary impairment	1	29
Additions for increases in the credit loss for which an other-than- temporary impairment previously was recognized and there was no intent to sell the security before recovery of its amortized cost basis	145	277
Reductions for securities sold during the period (realized)
Reductions for securities previously recognized in other comprehensive income because of intent to sell the security before recovery of its amortized cost basis
Reductions for increases in cash flows expected to be collected that are recognized over the remaining life of the security	(4)	(8)
Credit losses on securities held at the end of the period in accumulated other comprehensive income	$ 13,857	$ 13,857