Investments Gains and Losses by Security Type (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Gross Realized Gains	$ 1,875	$ 2,622	$ 390
Available-for-sale, Gross Realized Gains, Fair Value at Sale	69,737	94,931	116,923
Available-for-sale Securities, Gross Realized Losses	(1,328)	(1,795)	(410)
Available-for-sale, Gross Realized Losses, Fair Value at Sale	62,254	42,657	12,918
Available-for-sale Securities, Gross Realized Gain (Loss)	547	827	(20)
Available-for-sale, Gross Realized Gains (Losses), Fair Value at Sale	131,991	137,588	129,841
Fixed Maturities [Member]
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Gross Realized Gains	1,811	727	92
Available-for-sale, Gross Realized Gains, Fair Value at Sale	56,484	87,141	5,598
Available-for-sale Securities, Gross Realized Losses	(1,136)	(595)	(228)
Available-for-sale, Gross Realized Losses, Fair Value at Sale	24,464	38,485	11,389
Equity Securities
Schedule of Available-for-sale Securities [Line Items]
Available-for-sale Securities, Gross Realized Gains	64	1,895	298
Available-for-sale, Gross Realized Gains, Fair Value at Sale	13,253	7,790	111,325
Available-for-sale Securities, Gross Realized Losses	(192)	(1,200)	(182)
Available-for-sale, Gross Realized Losses, Fair Value at Sale	$ 37,790	$ 4,172	$ 1,529