Summary of Investments (Net Realized Investment Gains and Losses) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Gain (Loss) on Investments [Line Items]
Net realized investment gains (losses)	$ 1,190	$ 1,300	$ 7,250	$ 4,658
Available-for-sale Securities [Abstract]
Proceeds from sales	17,036	0	23,007	12,003
Gross realized gains	213	0	451	472
Gross realized losses	(139)	0	(139)	(25)
Fixed Maturities [Member] | Held-to-maturity [Member]
Gain (Loss) on Investments [Line Items]
Net realized investment gains (losses)	0	11	0	11
Fixed Maturities [Member] | Available-for-sale [Member]
Gain (Loss) on Investments [Line Items]
Net realized investment gains (losses)	626	91	2,531	2,414
Fixed Maturities [Member] | Trading Securities, Change in Fair Value [Member]
Gain (Loss) on Investments [Line Items]
Net realized investment gains (losses)	360	966	790	927
Fixed Maturities [Member] | Trading Securities, Sales [Member]
Gain (Loss) on Investments [Line Items]
Net realized investment gains (losses)	310	(64)	608	313
Equity Securities [Member] | Available-for-sale [Member]
Gain (Loss) on Investments [Line Items]
Net realized investment gains (losses)	(9)	0	3,739	697
Equity Securities [Member] | Trading Securities, Change in Fair Value [Member]
Gain (Loss) on Investments [Line Items]
Net realized investment gains (losses)	(97)	296	(116)	296
Equity Securities [Member] | Trading Securities, Sales [Member]
Gain (Loss) on Investments [Line Items]
Net realized investment gains (losses)	0	0	38	0
Other Long-term Investments [Member]
Gain (Loss) on Investments [Line Items]
Net realized investment gains (losses)	$ 0	$ 0	$ (340)	$ 0