Investments (Details 2) (USD $) In Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Other than temporary impairment credit losses
Total other-than-temporary impairment loss	$ 0	$ (316)	$ (4,677)	$ (316)
Portion recognized in other comprehensive income	0	(16)	(1,198)	(16)
Net other-than-temporary impairment loss recognized in earnings	0	(300)	(3,479)	(300)
Credit losses recognized in earnings with component in other comprehensive income
Balance at beginning of year	3,847	3,848	4,273	3,848
Securities previously impaired	0	300	1,597	300
Securities previously not impaired	0	0	1,882	0
Securities sold	0	0	(3,905)	0
Balance at September 30	$ 3,847	$ 4,148	$ 3,847	$ 4,148

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