Investments (Major Categories of Investment Gains and Losses) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Gain (Loss) on Investments [Line Items]
Net realized investment gains	$ 3,297	$ 1,703	$ 4,354	$ 2,774
Fixed Maturities [Member]
Gain (Loss) on Investments [Line Items]
Net realized investment gains	(16)	376	110	503
Equity Securities [Member]
Gain (Loss) on Investments [Line Items]
Net realized investment gains	(1)	1,528	928	2,263
Trading Securities [Member]
Gain (Loss) on Investments [Line Items]
Net realized investment gains	0	(1)	0	1
Other, Principally Real Estate [Member]
Gain (Loss) on Investments [Line Items]
Net realized investment gains	3,314	(200)	3,316	7
Other-than-Temporary Impairment [Member]
Gain (Loss) on Investments [Line Items]
Net realized investment gains	$ 0	$ 0	$ 0	$ 0