Consolidated Balance Sheets (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended	12 Months Ended
	Mar. 31, 2013	Dec. 31, 2012
Fixed maturities - available for sale, amortized cost	$ 5,380,387	$ 5,289,619
Equity securities - available for sale, cost	15	15
Other invested assets, cost	404,149	420,744
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	3,000	3,000
Common stock, shares issued	1,000	1,000
Common stock, shares outstanding	1,000	1,000
Accumulated other comprehensive income (loss), deferred income tax expense (benefit)	$ 92,429	$ 99,544
Senior Notes [Member]
Debt instrument, stated interest rate	5.40%	5.40%
Debt instrument, maturity date	Oct. 15, 2014	Oct. 15, 2014
Subordinated Debt [Member]
Debt instrument, stated interest rate	6.60%	6.60%
Debt instrument, maturity date	May 01, 2067	May 01, 2067