CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Cash flows provided by (used in) operating activities:
Net income (loss)	$ 730,388	$ (403,883)	$ 643,381
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Net realized (gains) losses on investments	(14,098)	188,359	270,803
Net realized and unrealized (gains) losses on derivative instruments	(5,221)	10,738	33,843
Amortization of premiums (discounts) on fixed maturities	169,353	120,130	60,869
(Income) loss from investment and operating affiliates	(114,314)	(103,039)	(172,474)
Impairment of goodwill	0	429,020	0
Share based compensation	47,472	41,225	44,057
Depreciation	57,280	49,800	40,423
Accretion of deposit liabilities	81,269	82,799	104,311
Changes in:
Unpaid losses and loss expenses	(287,972)	243,040	(207,526)
Future policy benefit reserves	(187,400)	(171,618)	(197,570)
Unearned premiums	182,963	95,393	(133,955)
Premiums receivable	(127,633)	(31,286)	94,649
Unpaid losses and loss expenses recoverable	305,675	(2,168)	(74,242)
Ceded unearned premiums	14,923	21,532	83,246
Reinsurance balances receivable	162,280	(49,286)	201,479
Deferred acquisition costs	(649)	(41,881)	12,235
Reinsurance balances payable	48,159	(31,846)	(253,213)
Deferred tax asset - net	(28,556)	(43,583)	104,111
Derivatives	7,252	93,796	123,027
Other assets	22,847	(24,747)	(68,513)
Other liabilities	50,342	(93,323)	(32,146)
Other	(58,254)	(51,970)	(82,039)
Total adjustments	325,718	731,085	(48,625)
Net cash provided by (used in) operating activities	1,056,106	327,202	594,756
Cash flows provided by (used in) investing activities:
Proceeds from sale of fixed maturities and short-term investments	3,604,792	5,091,375	5,206,690
Proceeds from redemption of fixed maturities and short-term investments	4,579,651	3,595,922	2,851,815
Proceeds from sale of equity securities	221,617	205,736	115,839
Purchases of fixed maturities and short term investments	(8,902,879)	(7,529,962)	(8,098,862)
Purchases of equity securities	(362,021)	(631,169)	(157,963)
Net dispositions of investment affiliates	(4,652)	136,281	319,108
Other investments, net	(79,101)	(36,080)	24,854
Net cash provided by (used in) investing activities	(942,593)	832,103	261,481
Cash flows provided by (used in) financing activities:
Proceeds from issuance of ordinary shares and exercise of stock options	5,413	576,333	1,182
Proceeds from issuance of Series D preference ordinary shares	0	349,180	0
Buybacks of ordinary shares	(402,930)	(667,022)	(522,024)
Repurchase of Redeemable Series C preference ordinary shares	0	(71,801)	(94,157)
Dividends paid on ordinary shares	(134,799)	(138,050)	(133,748)
Dividends paid on preference ordinary shares	0	0	(40,385)
Distributions to non-controlling interests	(78,987)	(71,483)	(37,392)
Proceeds from issuance of debt	0	395,859	0
Contribution from non-controlling interest	1,500	0	0
Repayment of debt	(600,000)	(575,000)	0
Deposit liabilities	(134,950)	(152,617)	(646,819)
Net cash provided by (used in) financing activities	(1,344,753)	(358,716)	(1,473,343)
Effects of exchange rate changes on foreign currency cash	24,493	1,668	(3,723)
Increase (decrease) in cash and cash equivalents	(1,206,747)	802,257	(620,829)
Cash and cash equivalents beginning of year	3,825,125	3,022,868	3,643,697
Cash and cash equivalents end of year	2,618,378	3,825,125	3,022,868
Supplemental cash flow disclosures:
Net taxes paid	34,465	106,666	75,429
Interest paid on notes payable and debt	116,689	149,133	162,086
Series D preference ordinary shares
Cash flows provided by (used in) financing activities:
Repurchase of preference ordinary shares	0	(3,650)	0
Series E ordinary preference shares
Cash flows provided by (used in) financing activities:
Repurchase of preference ordinary shares	$ 0	$ (465)	$ 0