Other Comprehensive Income (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014		Mar. 31, 2013		Dec. 31, 2013
Other comprehensive income (before tax) [Abstract]
Change in unrealized gains and losses on investments	$ 39,661		$ (10,539)
Benefit plan adjustments	(1,486)
Unrealized foreign currency translation adjustment	1,931		486
Other comprehensive income (loss)	40,106		(10,053)
Other comprehensive income (tax) [Abstract]
Change in unrealized gains and losses on investments	(13,871)		3,592
Benefit plan adjustments	520
Unrealized foreign currency translation adjustment	(678)		(170)
Other comprehensive income (loss)	(14,029)		3,422
Other comprehensive income (valuation allowance) [Abstract]
Change in unrealized investment gains and losses, net	13,808		(3,007)
Benefit plan adjustments	(520)
Other comprehensive income foreign currency translation valuation allowance	0		0
Other comprehensive income (loss)	13,288		(3,007)
Other comprehensive income (net of tax) [Abstract]
Change in unrealized investment gains and losses on investments	39,598		(9,954)
Benefit plan adjustments	(1,486)
Unrealized foreign currency translation adjustment	1,253		316
Other comprehensive income (loss)	39,365		(9,638)
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period, before tax	(77,216)		2,484
Other comprehensive income (loss) before reclassifications	38,603		(7,981)
Amounts reclassified from accumulated other comprehensive income (loss)	(1,503)		2,072
Net current period other comprehensive income (loss)	40,106		(10,053)
Balance at end of period, before tax	(37,110)		(7,569)
Tax effect	(41,251)	[1]	(50,232)	[1]	(40,510)	[1]
Total accumulated other comprehensive income (loss), net of tax	(78,361)		(57,801)		(117,726)
Tax Effect due to valuation allowance (in hundredths)	35.00%
Unrealized gains and losses on available-for-sale securities [Member]
Other comprehensive income (before tax) [Abstract]
Other comprehensive income (loss)	39,661		(10,539)
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period, before tax	(84,634)		41,541
Other comprehensive income (loss) before reclassifications	36,672		(8,467)
Amounts reclassified from accumulated other comprehensive income (loss)	(2,989)	[2]	2,072	[2]
Net current period other comprehensive income (loss)	39,661		(10,539)
Balance at end of period, before tax	(44,973)		31,002
Tax effect	(64,119)	[1]	(66,054)	[1]	(64,056)	[1]
Total accumulated other comprehensive income (loss), net of tax	(109,092)		(35,052)		(148,690)
Defined benefit plans [Member]
Other comprehensive income (before tax) [Abstract]
Other comprehensive income (loss)	(1,486)		0
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period, before tax	(3,766)		(71,804)
Other comprehensive income (loss) before reclassifications	0		0
Amounts reclassified from accumulated other comprehensive income (loss)	1,486	[3]	0
Net current period other comprehensive income (loss)	(1,486)		0
Balance at end of period, before tax	(5,252)		(71,804)
Tax effect	26,940	[1]	26,940	[1]	26,940	[1]
Total accumulated other comprehensive income (loss), net of tax	21,688		(44,864)		23,174
Foreign currency translation [Member]
Other comprehensive income (before tax) [Abstract]
Other comprehensive income (loss)	1,931		486
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period, before tax	11,184		32,747
Other comprehensive income (loss) before reclassifications	1,931		486
Amounts reclassified from accumulated other comprehensive income (loss)	0		0
Net current period other comprehensive income (loss)	1,931		486
Balance at end of period, before tax	13,115		33,233
Tax effect	(4,072)	[1]	(11,118)	[1]	(3,394)	[1]
Total accumulated other comprehensive income (loss), net of tax	$ 9,043		$ 22,115		$ 7,790

[1] Tax effect does not approximate 35% due to amounts of tax benefits not provided in various periods due to our tax valuation allowance.

[2] During the three months ended March 31, 2014 and 2013, net unrealized (losses) gains of ($3.0) million and $2.1 million, respectively, were reclassified to the Consolidated Statement of Operations and included in Realized investment gains (losses).

[3] During the three months ended March 31, 2014, other comprehensive income related to benefit plans of $1.5 million was reclassified to the Consolidated Statement of Operations and included in Underwriting and other expenses, net.