Statements of Comprehensive Income (Loss) Statements of Comprehensive Income (Loss) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2015		Mar. 31, 2014
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Accumulated Other Comprehensive Income (Loss), Beginning of Period	$ 183,550
Other comprehensive income (loss)	(31,514)		69,510
Accumulated Other Comprehensive Income (Loss), End of Period	152,058
Net realized investment gains	19,044		52,754
Income before income taxes	168,717		247,585
Income before taxes	551,046		515,166
Tax effect	(50,273)		(77,901)
After-tax amounts reclassified	118,444		169,684
Unrealized investment gains, pre-tax	24,536		112,290
Unrealized investment gains, tax effect	(8,245)		(39,346)
Unrealized investment gains, after-tax amounts	16,291		72,944
Currency translation adjustment, pre-tax	(47,805)		(4,025)
Currency translation adjustment, tax effect	0		0
Change in unrealized currency translation adjustments	(47,805)		(4,025)
Net pension asset, pre-tax	0		909
Net pension asset, tax effect	0		(318)
Net pension asset, after-tax amounts	0		591
Other comprehensive income (loss), pre-tax	(23,269)		109,174
Other comprehensive income (loss), tax effect	(8,245)		(39,664)
Accumulated Net Unrealized Investment Gain (Loss) [Member]
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Accumulated Other Comprehensive Income (Loss), Beginning of Period	306,199		256,566
Other comprehensive income (loss) before reclassifications	24,592		77,443
Amounts reclassified from AOCI	(8,301)		(4,499)
Other comprehensive income (loss)	16,291		72,944
Unrealized investment gain related to non-controlling interest	22		(18)
Accumulated Other Comprehensive Income (Loss), End of Period	322,512		329,492
Currency Translation Adjustments [Member]
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Accumulated Other Comprehensive Income (Loss), Beginning of Period	(122,649)		(60,524)
Other comprehensive income (loss) before reclassifications	(47,805)		(4,025)
Amounts reclassified from AOCI	0		0
Other comprehensive income (loss)	(47,805)		(4,025)
Unrealized investment gain related to non-controlling interest	0		0
Accumulated Other Comprehensive Income (Loss), End of Period	(170,454)		(64,549)
Change in unrealized currency translation adjustments	(47,805)		(4,025)
Net Pension Asset [Member]
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Accumulated Other Comprehensive Income (Loss), Beginning of Period	0		(6,651)
Other comprehensive income (loss) before reclassifications	0		0
Amounts reclassified from AOCI	0		591
Other comprehensive income (loss)	0		591
Unrealized investment gain related to non-controlling interest	0		0
Accumulated Other Comprehensive Income (Loss), End of Period	0		(6,060)
Accumulated Other Comprehensive Income (Loss) [Member]
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Accumulated Other Comprehensive Income (Loss), Beginning of Period	183,550		189,391
Other comprehensive income (loss) before reclassifications	(23,213)		73,418
Amounts reclassified from AOCI	(8,301)		(3,908)
Other comprehensive income (loss)	(31,514)		69,510
Unrealized investment gain related to non-controlling interest	22
Accumulated Other Comprehensive Income (Loss), End of Period	152,058		258,883
Reclassification out of Accumulated Other Comprehensive Income [Member] | Accumulated Net Unrealized Investment Gain (Loss) [Member]
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Net realized investment gains	(12,771)	[1]	(6,921)	[1]
Tax effect	4,470	[2]	2,422	[2]
After-tax amounts reclassified	(8,301)		(4,499)
Reclassification out of Accumulated Other Comprehensive Income [Member] | Currency Translation Adjustments [Member]
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Income before income taxes	0		0
Tax effect	0	[2]	0	[2]
After-tax amounts reclassified	0		0
Reclassification out of Accumulated Other Comprehensive Income [Member] | Net Pension Asset [Member]
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Income before taxes	0	[3]	909	[3]
Tax effect	0	[2]	(318)	[2]
After-tax amounts reclassified	0		591
Reclassification out of Accumulated Other Comprehensive Income [Member] | Accumulated Other Comprehensive Income (Loss) [Member]
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Income before income taxes	(12,771)		(6,012)
Tax effect	4,470	[2]	2,104	[2]
After-tax amounts reclassified	$ (8,301)		$ (3,908)

[1] Net investment gains in the consolidated statements of

[2] Income tax expense in the consolidated statements of income.

[3] Other operating costs and expenses in the consolidated statements of income.