Taxation (Tables)

12 Months Ended

Dec. 31, 2012

Disclosure - Taxation [Abstract]

Components of income tax expense

		2012		2011		2010
Current income tax expense
U.S.	$	29,196	$	82,065	$	28,180
Non U.S.		115,669		72,268		36,706
Total current income tax expense	$	144,865	$	154,333	$	64,886
Deferred income tax expense (benefit)
U.S.	$	48,740	$	(36,780)	$	46,988
Non U.S.		6,717		(8,112)		4,738
Total deferred income tax expense (benefit)	$	55,457	$	(44,892)	$	51,726
Unrecognized tax expense (benefit)
U.S.	$	(623)	$	81	$	0
Non U.S.		4,585		(40,550)		12,172
Total unrecognized tax expense (benefit)	$	3,962	$	(40,469)	$	12,172
Total income tax expense
U.S.	$	77,313	$	45,366	$	75,168
Non U.S.		126,971		23,606		53,616
Total income tax expense	$	204,284	$	68,972	$	128,784

Schedule of Income before Income Tax, Domestic and Foreign [Table Text Block]

		2012		2011		2010
Domestic (Bermuda)	$	661,648	$	(634,310)	$	441,074
Foreign		677,150		182,991		540,262
Income (loss) before taxes	$	1,338,798	$	(451,319)	$	981,336

Reconciliation of effective tax rate

Reconciliation of effective tax rate (% of income (loss) before taxes)
Expected tax rate	0.0	%	0.0	%	0.0	%
Foreign taxes at local expected tax rates	14.6		(7.2)		14.9
Impact of foreign exchange (losses) gains	(0.4)		0.4		(3.4)
Unrecognized tax benefit	0.3		9.0		1.2
Tax-exempt income and expenses not deductible	(0.3)		(11.6)		(0.7)
Impact of enacted changes in tax laws	0.7		0.0		(1.9)
Foreign branch tax	(0.7)		(5.7)		(0.2)
Valuation allowance	1.2		(1.9)		2.0
Other	(0.1)		1.7		1.2
Actual tax rate	15.3	%	(15.3)	%	13.1	%

Significant components of net deferred tax assets and liabilities

		2012		2011
Deferred tax assets
Discounting of loss reserves and adjustment to life policy reserves	$	50,341	$	84,977
Foreign tax credit carryforwards		37,569		15,005
Tax loss carryforwards		47,373		31,823
Unearned premiums		17,856		19,152
Other deferred tax assets		36,424		35,040
		189,563		185,997
Valuation allowance		(47,412)		(29,201)
Deferred tax assets		142,151		156,796
Deferred tax liabilities
Deferred acquisition costs		46,311		42,913
Goodwill and other intangibles		106,445		71,000
Equalization reserves		122,930		104,884
Unrealized appreciation and timing differences on investments		141,856		105,817
Other deferred tax liabilities		24,968		32,397
Deferred tax liabilities		442,510		357,011
Net deferred tax liabilities	$	(300,359)	$	(200,215)

Schedule Of Net Tax Assets And Liabilities Table [Text Block]

		2012		2011
Net tax assets	$	25,098	$	66,574
Net tax liabilities		(387,647)		(297,153)
Net tax liabilities	$	(362,549)	$	(230,579)
		2012		2011
Net current tax liabilities	$	(45,606)	$	(18,074)
Net deferred tax liabilities		(300,359)		(200,215)
Net unrecognized tax benefit		(16,584)		(12,290)
Net tax liabilities	$	(362,549)	$	(230,579)

Total amount of unrecognized tax benefits

				Changes in tax		Tax positions		Change as a		Impact of the
				positions taken		taken		result of a lapse		change in
		January 1,		during a prior		during the		of the statute		foreign currency		December 31,
		2012		period		current period		of limitations		exchange rates		2012
Unrecognized tax benefits
	that, if recognized, would impact
	the effective tax rate	$	11,879	$	1,571	$	3,080	$	(1,057)	$	311	$	15,784
Interest and penalties recognized
	on the above		411		504		8		(144)		21		800
Total unrecognized tax benefits, including
	interest and penalties	$	12,290	$	2,075	$	3,088	$	(1,201)	$	332	$	16,584

				Changes in tax		Tax positions		Change as a		Impact of the
				positions taken		taken		result of a lapse		change in
		January 1,		during a prior		during the		of the statute		foreign currency		December 31,
		2011		period		current period		of limitations		exchange rates		2011
Unrecognized tax benefits
	that, if recognized, would impact
	the effective tax rate	$	51,529	$	3,194	$	3,788	$	(47,886)	$	1,254	$	11,879
Interest and penalties recognized
	on the above		0		435		0		0		(24)		411
Total unrecognized tax benefits, including
	interest and penalties	$	51,529	$	3,629	$	3,788	$	(47,886)	$	1,230	$	12,290

				Changes in tax		Tax positions		Change as a		Impact of the
				positions taken		taken		result of a lapse		change in
		January 1,		during a prior		during the		of the statute		foreign currency		December 31,
		2010		period		current period		of limitations		exchange rates		2010
Unrecognized tax benefits
	that, if recognized, would impact
	the effective tax rate	$	41,935	$	13,215	$	2,578	$	(3,254)	$	(2,945)	$	51,529
Interest and penalties recognized
	on the above		544		104		0		(471)		(177)		0
Total unrecognized tax benefits, including
	interest and penalties	$	42,479	$	13,319	$	2,578	$	(3,725)	$	(3,122)	$	51,529