Investments, Gain (Loss) on Investments (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Gain (Loss) on Investments [Line Items]
Change in net unrealized appreciation (depreciation)	$ (126,173)	$ (78,546)	$ 31,662
Gross realized gains, gross realized losses and impairment losses [Abstract]
Gross realized gains	11,043	213,827	158,659
Gross realized losses	(4,984)	(16,108)	(15,229)
Impairment losses	(328)	(2,310)	(715)
Net realized gains (losses) on securities	5,731	195,409	142,715
Available-for-sale Securities [Member]
Gain (Loss) on Investments [Line Items]
Net realized investment gains (losses) and OTTI on investments	5,731	195,409	142,715
Available-for-sale Securities [Member] | Fixed Maturities [Member]
Gain (Loss) on Investments [Line Items]
Net realized investment gains (losses) and OTTI on investments	3,274	195,652	142,284
Change in net unrealized appreciation (depreciation)	(126,020)	(78,604)	31,576
Available-for-sale Securities [Member] | Equity Securities [Member]
Gain (Loss) on Investments [Line Items]
Net realized investment gains (losses) and OTTI on investments	1,068	487	330
Change in net unrealized appreciation (depreciation)	(153)	58	86
Available-for-sale Securities [Member] | Other [Member]
Gain (Loss) on Investments [Line Items]
Net realized investment gains (losses) and OTTI on investments	1,389	(730)	101
Change in net unrealized appreciation (depreciation)	$ 0	$ 0	$ 0