BALANCE SHEETS (Parenthetical) (USD $) In Thousands, except Share data, unless otherwise specified	Sep. 30, 2013	Dec. 31, 2012
Fixed maturity available-for-sale securities, amortized cost	$ 1,839,285	$ 1,754,007
Equity available-for-sale securities, cost	$ 34,162	$ 38,996
Common stock, par value	$ 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