Accumulated Other Comprehensive Income (Loss) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended			6 Months Ended
	Jun. 30, 2013		Jun. 30, 2012	Jun. 30, 2013		Jun. 30, 2012
Schedule of accumulated other comprehensive income (loss)
Unrealized Gains and Losses on Fixed Maturities and Equity Securities, Beginning balance	$ 374,066	[1],[2]		$ 382,400	[1],[2]
Unrealized Gains and Losses on Fixed Maturities and Equity Securities, Other comprehensive income (loss) before reclassifications	(167,198)	[1],[2]		(171,072)	[1],[2]
Unrealized Gains and Losses on Fixed Maturities and Equity Securities, Amounts reclassified from accumulated other comprehensive income	(10,021)	[1],[2]		(14,481)	[1],[2]
Unrealized Gains and Losses on Fixed Maturities and Equity Securities, Net current-period other comprehensive income (loss)	(177,219)	[1],[2]	53,839	(185,553)	[1],[2]	66,422
Unrealized Gains and Losses on Fixed Maturities and Equity Securities, Ending balance	196,847	[1],[2]		196,847	[1],[2]
Defined Benefit Plans, Beginning balance	(15,311)	[1]		15,311	[1]
Defined Benefit Plans, Ending balance	15,311	[1]		15,311	[1]
Total, Beginning balance	358,755	[1]		367,089	[1]
Total, Other comprehensive income (loss) before reclassifications	(167,198)	[1]		(171,072)	[1]
Total, Amounts reclassified from accumulated other comprehensive income	(10,021)	[1]		(14,481)	[1]
Total, Net current-period other comprehensive income (loss)	(177,219)	[1]	53,839	(185,553)	[1]	66,422
Total, Ending balance	$ 181,536	[1]		$ 181,536	[1]

[1] All amounts are net of tax.

[2] The pretax amounts reclassified from accumulated other comprehensive income, $15,417 and $22,279, are included in net realized investment gains and the related tax expenses, $5,396 and $7,798, are included in income tax expense in the Consolidated Statements of Operations for the three and six months ended June 30, 2013, respectively.