Summary of Investments (Details 7) (Fixed maturities, USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012	Jun. 30, 2013
Fixed maturities
Bifurcated credit loss:
Beginning balance	$ 186,999	$ 167,788	$ 186,999	$ 167,961
Additional credit loss recognized on securities previously impaired		173
Reductions due to sales, maturities, or payoffs during the period	(23,640)		(23,640)
Ending balance	$ 163,359	$ 167,961	$ 163,359	$ 167,961