Other Comprehensive Income (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended				6 Months Ended
	Jun. 30, 2014		Jun. 30, 2013		Jun. 30, 2014		Jun. 30, 2013		Dec. 31, 2013
Other comprehensive income (before tax) [Abstract]
Change in unrealized gains and losses on investments	$ 44,818		$ (99,092)		$ 84,479		$ (109,631)
Benefit plan adjustments	(1,980)				(3,466)
Unrealized foreign currency translation adjustment	904		(19,255)		2,835		(18,769)
Other comprehensive income (loss)	43,742		(118,347)		83,848		(128,400)
Other comprehensive income (tax) [Abstract]
Change in unrealized gains and losses on investments	(15,634)		34,520		(29,505)		38,112
Benefit plan adjustments	693				1,213
Unrealized foreign currency translation adjustment	(317)		6,743		(995)		6,573
Other comprehensive income (loss)	(15,258)		41,263		(29,287)		44,685
Other comprehensive income (valuation allowance) [Abstract]
Change in unrealized investment gains and losses, net	15,317		(33,547)		29,125		(36,554)
Benefit plan adjustments	(693)				(1,213)
Other comprehensive income foreign currency translation valuation allowance	0		0		0		0
Other comprehensive income (loss)	14,624		(33,547)		27,912		(36,554)
Other comprehensive income (net of tax) [Abstract]
Change in unrealized investment gains and losses on investments	44,501		(98,119)		84,099		(108,073)
Benefit plan adjustments	(1,980)				(3,466)
Unrealized foreign currency translation adjustment	587		(12,512)		1,840		(12,196)
Other comprehensive income (loss)	43,108		(110,631)		82,473		(120,269)
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period, before tax	(37,110)		(7,569)		(77,216)		2,484
Other comprehensive income (loss) before reclassifications	43,826		(116,193)		81,383		(122,868)
Amounts reclassified from accumulated other comprehensive income (loss)	84		2,154		(2,465)		5,532
Net current period other comprehensive income (loss)	43,742		(118,347)		83,848		(128,400)
Balance at end of period, before tax	6,632		(125,916)		6,632		(125,916)
Tax effect	(41,885)	[1]	(42,516)	[1]	(41,885)	[1]	(42,516)	[1]	(40,510)	[1]
Total accumulated other comprehensive income (loss), net of tax	(35,253)		(168,432)		(35,253)		(168,432)		(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)	44,818		(99,092)		84,479		(109,631)
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period, before tax	(44,973)		31,002		(84,634)		41,541
Other comprehensive income (loss) before reclassifications	42,922		(96,938)		78,548		(104,099)
Amounts reclassified from accumulated other comprehensive income (loss)	(1,896)	[2]	2,154	[2]	(5,931)	[2]	5,532	[2]
Net current period other comprehensive income (loss)	44,818		(99,092)		84,479		(109,631)
Balance at end of period, before tax	(155)		(68,090)		(155)		(68,090)
Tax effect	(64,436)	[1]	(65,082)	[1]	(64,436)	[1]	(65,082)	[1]	(64,056)	[1]
Total accumulated other comprehensive income (loss), net of tax	(64,591)		(133,172)		(64,591)		(133,172)		(148,690)
Defined benefit plans [Member]
Other comprehensive income (before tax) [Abstract]
Other comprehensive income (loss)	(1,980)		0		(3,466)		0
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period, before tax	(5,252)		(71,804)		(3,766)		(71,804)
Other comprehensive income (loss) before reclassifications	0		0		0		0
Amounts reclassified from accumulated other comprehensive income (loss)	1,980	[3]	0		3,466	[3]	0
Net current period other comprehensive income (loss)	(1,980)		0		(3,466)		0
Balance at end of period, before tax	(7,232)		(71,804)		(7,232)		(71,804)
Tax effect	26,940	[1]	26,940	[1]	26,940	[1]	26,940	[1]	26,940	[1]
Total accumulated other comprehensive income (loss), net of tax	19,708		(44,864)		19,708		(44,864)		23,174
Foreign currency translation [Member]
Other comprehensive income (before tax) [Abstract]
Other comprehensive income (loss)	904		(19,255)		2,835		(18,769)
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period, before tax	13,115		33,233		11,184		32,747
Other comprehensive income (loss) before reclassifications	904		(19,255)		2,835		(18,769)
Amounts reclassified from accumulated other comprehensive income (loss)	0		0		0		0
Net current period other comprehensive income (loss)	904		(19,255)		2,835		(18,769)
Balance at end of period, before tax	14,019		13,978		14,019		13,978
Tax effect	(4,389)	[1]	(4,374)	[1]	(4,389)	[1]	(4,374)	[1]	(3,394)	[1]
Total accumulated other comprehensive income (loss), net of tax	$ 9,630		$ 9,604		$ 9,630		$ 9,604		$ 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 and six months ended June 30, 2014, net unrealized losses of ($1.9) million and ($5.9) million, respectively, were reclassified to the Consolidated Statement of Operations and included in Realized investment gains, net. During the three and six months ended June 30, 2013, net unrealized gains of $2.2 million and $5.5 million, respectively were reclassified to the Consolidated Statement of Operations and included in Realized investment gains, net.

[3] During the three and six months ended June 30, 2014, other comprehensive income related to benefit plans of $2.0 million and $3.5 million, respectively, was reclassified to the Consolidated Statement of Operations and included in Underwriting and other expenses, net.