Other Comprehensive Income (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended				9 Months Ended
	Sep. 30, 2014		Sep. 30, 2013		Sep. 30, 2014		Sep. 30, 2013		Dec. 31, 2013
Other comprehensive income (before tax) [Abstract]
Change in unrealized gains and losses on investments	$ (17,377)		$ 7,163		$ 67,102		$ (102,468)
Benefit plan adjustments	(1,732)				(5,198)
Unrealized foreign currency translation adjustment	(3,835)		2,901		(1,000)		(15,868)
Other comprehensive income (loss)	(22,944)		10,064		60,904		(118,336)
Other comprehensive income (tax) [Abstract]
Change in unrealized gains and losses on investments	6,069		(2,526)		(23,436)		35,586
Benefit plan adjustments	606				1,819
Unrealized foreign currency translation adjustment	1,345		(1,016)		350		5,557
Other comprehensive income (loss)	8,020		(3,542)		(21,267)		41,143
Other comprehensive income (valuation allowance) [Abstract]
Change in unrealized investment gains and losses, net	(5,993)		2,640		23,132		(33,914)
Benefit plan adjustments	(606)				(1,819)
Other comprehensive income foreign currency translation valuation allowance	0		0		0		0
Other comprehensive income (loss)	(6,599)		2,640		21,313		(33,914)
Other comprehensive income (net of tax) [Abstract]
Change in unrealized investment gains and losses on investments	(17,301)		7,277		66,798		(100,796)
Benefit plan adjustments	(1,732)				(5,198)
Unrealized foreign currency translation adjustment	(2,490)		1,885		(650)		(10,311)
Other comprehensive income (loss)	(21,523)		9,162		60,950		(111,107)
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period, before tax	6,632		(125,916)		(77,216)		2,484
Other comprehensive income (loss) before reclassifications	(22,052)		7,297		55,332		(111,456)
Amounts reclassified from accumulated other comprehensive income (loss)	892		(2,767)		(5,572)		6,880
Net current period other comprehensive income (loss)	(22,944)		10,064		60,904		(118,336)
Balance at end of period, before tax	(16,312)		(115,852)		(16,312)		(115,852)
Tax effect	(40,464)	[1]	(43,418)	[1]	(40,464)	[1]	(43,418)	[1]	(40,510)	[1]
Total accumulated other comprehensive income (loss), net of tax	(56,776)		(159,270)		(56,776)		(159,270)		(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)	(17,377)		7,163		67,102		(102,468)
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period, before tax	(155)		(68,090)		(84,634)		41,541
Other comprehensive income (loss) before reclassifications	(18,217)		4,396		56,332		(95,588)
Amounts reclassified from accumulated other comprehensive income (loss)	(840)	[2]	(2,767)	[2]	(10,770)	[2]	6,880	[2]
Net current period other comprehensive income (loss)	(17,377)		7,163		67,102		(102,468)
Balance at end of period, before tax	(17,532)		(60,927)		(17,532)		(60,927)
Tax effect	(64,360)	[1]	(64,968)	[1]	(64,360)	[1]	(64,968)	[1]	(64,056)	[1]
Total accumulated other comprehensive income (loss), net of tax	(81,892)		(125,895)		(81,892)		(125,895)		(148,690)
Defined benefit plans [Member]
Other comprehensive income (before tax) [Abstract]
Other comprehensive income (loss)	(1,732)		0		(5,198)		0
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period, before tax	(7,232)		(71,804)		(3,766)		(71,804)
Other comprehensive income (loss) before reclassifications	0		0		0		0
Amounts reclassified from accumulated other comprehensive income (loss)	1,732	[3]	0		5,198	[3]	0
Net current period other comprehensive income (loss)	(1,732)		0		(5,198)		0
Balance at end of period, before tax	(8,964)		(71,804)		(8,964)		(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	17,976		(44,864)		17,976		(44,864)		23,174
Foreign currency translation [Member]
Other comprehensive income (before tax) [Abstract]
Other comprehensive income (loss)	(3,835)		2,901		(1,000)		(15,868)
Accumulated Other Comprehensive Income Loss [Line Items]
Balance at beginning of period, before tax	14,019		13,978		11,184		32,747
Other comprehensive income (loss) before reclassifications	(3,835)		2,901		(1,000)		(15,868)
Amounts reclassified from accumulated other comprehensive income (loss)	0		0		0		0
Net current period other comprehensive income (loss)	(3,835)		2,901		(1,000)		(15,868)
Balance at end of period, before tax	10,184		16,879		10,184		16,879
Tax effect	(3,044)	[1]	(5,390)	[1]	(3,044)	[1]	(5,390)	[1]	(3,394)	[1]
Total accumulated other comprehensive income (loss), net of tax	$ 7,140		$ 11,489		$ 7,140		$ 11,489		$ 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 nine months ended September 30, 2014, net unrealized losses of ($0.8) million and ($10.8) million, respectively, were reclassified to the Consolidated Statement of Operations and included in Realized investment gains, net. During the three and nine months ended September 30, 2013, net unrealized (losses) gains of ($2.8) million and $6.9 million, respectively were reclassified to the Consolidated Statement of Operations and included in Realized investment gains, net.

[3] During the three and nine months ended September 30, 2014, other comprehensive income related to benefit plans of $1.7 million and $5.2 million, respectively, was reclassified to the Consolidated Statement of Operations and included in Underwriting and other expenses, net.