Investments (All Other Net Unrealized Investment Gains and Losses in AOCI) (Details) (USD $) In Thousands, unless otherwise specified			6 Months Ended
	Jun. 30, 2012	Dec. 31, 2011	Jun. 30, 2012 Other Net Unrealized Investment Gains and Losses [Member] Accumulated Net Unrealized Investment Gain (Loss) Pre Tax [Member]	Jun. 30, 2012 Other Net Unrealized Investment Gains and Losses [Member] Deferred Policy Acquisition Costs and Other Costs	Jun. 30, 2012 Other Net Unrealized Investment Gains and Losses [Member] Deferred Income Tax Liability Benefit [Member]	Jun. 30, 2012 Other Net Unrealized Investment Gains and Losses [Member] Accumulated Net Unrealized Investment Gain (Loss) [Member]
Balance	$ 148,537	$ 160,712	$ 441,680	$ (192,122)	$ (88,164)	$ 161,394
Net investment gains (losses) on investments arising during the period			(31,138)	0	10,898	(20,240)
Reclassification adjustment for (gains) losses included in net income			(13,850)	0	4,848	(9,002)
Impact of net unrealized investment (gains) losses on deferred policy acquisition costs			0	24,940	(8,729)	16,211
Balance	$ 148,537	$ 160,712	$ 396,692	$ (167,182)	$ (81,147)	$ 148,363