UNAUDITED CONSOLIDATED STATEMENTS OF INCOME (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Revenues:
Net premiums earned	$ 1,334,000us-gaap_PremiumsEarnedNet	$ 1,488,839us-gaap_PremiumsEarnedNet
Net investment income	208,513us-gaap_InvestmentIncomeNet	233,189us-gaap_InvestmentIncomeNet
Realized investment gains (losses):
Total net realized gains (losses) on investments, and net unrealized gains (losses) on investments Trading - Life Funds Withheld Assets	52,891us-gaap_MarketableSecuritiesGainLoss	19,229us-gaap_MarketableSecuritiesGainLoss
Net realized and unrealized gains (losses) on derivative instruments	16,521	1,810
Income (loss) from investment fund affiliates	35,329	33,303
Fee income and other	4,728us-gaap_FeesAndCommissionsOther	11,454us-gaap_FeesAndCommissionsOther
Total revenues	1,422,615us-gaap_Revenues	1,787,824us-gaap_Revenues
Expenses:
Net losses and loss expenses incurred	769,827	831,505
Claims and policy benefits	19,387	113,587
Acquisition costs	153,696	199,414
Operating expenses	325,656us-gaap_OperatingExpenses	310,424us-gaap_OperatingExpenses
Foreign exchange (gains) losses	27,390	10,441
Interest expense	51,438us-gaap_InterestExpense	42,941us-gaap_InterestExpense
Total expenses	1,347,394us-gaap_BenefitsLossesAndExpenses	1,508,312us-gaap_BenefitsLossesAndExpenses
Income (loss) before income tax and income (loss) from operating affiliates	75,221	279,512
Income (loss) from operating affiliates	22,668	46,285
Provision (benefit) for income tax	24,218us-gaap_IncomeTaxExpenseBenefit	34,321us-gaap_IncomeTaxExpenseBenefit
Net income (loss)	73,671us-gaap_ProfitLoss	291,476us-gaap_ProfitLoss
Non-controlling interests	37,390	35,759
Net income (loss) attributable to ordinary shareholders	36,281us-gaap_NetIncomeLoss	255,717us-gaap_NetIncomeLoss
Weighted average ordinary shares outstanding - basic	255,724	276,337
Weighted average ordinary shares outstanding - diluted	260,704	280,458
Earnings (loss) per ordinary share and ordinary share equivalent - basic (in dollars per share)	$ 0.14us-gaap_EarningsPerShareBasic	$ 0.93us-gaap_EarningsPerShareBasic
Earnings (loss) per ordinary share and ordinary share equivalent - diluted (in dollars per share)	$ 0.14us-gaap_EarningsPerShareDiluted	$ 0.91us-gaap_EarningsPerShareDiluted
Excluding Life Funds Withheld Assets
Revenues:
Net investment income	158,094	233,189
Realized investment gains (losses):
Net realized gains (losses) on investments sold	15,178	22,956
Other-than-temporary impairments on investments	(10,515)	(2,276)
Other-than-temporary impairments on investments transferred to (from) other comprehensive income	(61)	(1,451)
Life Funds Withheld Assets
Revenues:
Net investment income	50,419	0
Realized investment gains (losses):
Net realized gains (losses) on investments sold	52,738	0
Other-than-temporary impairments on investments	(5,209)	0
Net unrealized gains (losses) on investments, trading securities	760	0
Net realized and unrealized gains (losses) on derivative instruments	$ (229,367)	$ 0

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