Unaudited Interim Consolidated Statements of Financial Position (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Statement of Financial Position [Abstract]
Fixed maturities, available-for-sale, amortized cost	$ 7,120,844	$ 6,775,806
Equity maturities, available-for-sale, amortized cost	$ 59,599	$ 54,609
Common Stock, Par Value (in dollars per share)	$ 10	$ 10
Common Stock, Shares, Authorized	1,000,000	1,000,000
Common Stock, Shares, Issued	250,000	250,000
Common Stock, Shares, Outstanding	250,000	250,000