Investments (Details 5) (USD $) In Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2011	Sep. 30, 2010
Realized pretax gains-losses-on the sale of investments excluding temporary impairment losses
Gains	$ 4,219	$ 1,282	$ 8,538	$ 8,877
Losses	(1,545)	(225)	(5,369)	(980)
Net realized investment gain (loss)	2,674	1,057	3,169	7,897
Fixed income securities [Member]
Realized pretax gains-losses-on the sale of investments excluding temporary impairment losses
Gains	4,217	1,282	8,532	8,875
Losses	(1,545)	(225)	(5,359)	(824)
Net fixed income securities	2,672	1,057	3,173	8,051
Other Investments [Member]
Realized pretax gains-losses-on the sale of investments excluding temporary impairment losses
Gains	2	0	6	2
Losses	0	0	(10)	(156)
Net other investments	$ 2	$ 0	$ (4)	$ (154)