Investments Gains and Losses by Security Type (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Gross Realized Gain (Loss)	$ 2,160	$ 158	$ 4,346
Year to Date [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Gross Realized Gains	2,322	241	4,427
Available-for-sale, Gross Realized Gains, Fair Value at Sale	30,906	21,868	108,368
Available-for-sale Securities, Gross Realized Losses	(162)	(83)	(81)
Available-for-sale, Gross Realized Losses, Fair Value at Sale	9,634	3,526	17,010
Available-for-sale Securities, Gross Realized Gain (Loss)	2,160	158	4,346
Available-for-sale, Gross Realized Gains (Losses), Fair Value at Sale	40,540	25,394	125,378
Fixed Maturities [Member] | Year to Date [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Gross Realized Gains	2,043	231	4,278
Available-for-sale, Gross Realized Gains, Fair Value at Sale	28,999	21,803	105,637
Available-for-sale Securities, Gross Realized Losses	(141)	(58)	(43)
Available-for-sale, Gross Realized Losses, Fair Value at Sale	9,243	3,191	15,700
Equity Securities [Member] | Year to Date [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Gross Realized Gains	279	10	149
Available-for-sale, Gross Realized Gains, Fair Value at Sale	1,907	65	2,731
Available-for-sale Securities, Gross Realized Losses	(21)	(25)	(38)
Available-for-sale, Gross Realized Losses, Fair Value at Sale	$ 391	$ 335	$ 1,310