Investments (Tables)

3 Months Ended

Mar. 31, 2012

Available For Sale Securities And Held To Maturity Securities [Table Text Block]

			Included in AOCI
					Gross Unrealized Losses
March 31, 2012 (U.S. dollars in thousands)	Cost or Amortized Cost		Gross Unrealized Gains		Related to Changes in Estimated Fair Value			Non-credit Related OTTI			Fair Value
Fixed maturities - AFS
U.S. Government and Government-Related/Supported (1)	$	2,130,093	$	110,804	$	(7,077	)	$	-		$	2,233,820
Corporate (2) (3) (4)		9,854,093		557,350		(148,569	)		(42,882	)		10,219,992
RMBS – Agency		5,238,075		163,999		(8,683	)		-			5,393,391
RMBS – Non-Agency		792,800		23,227		(71,292	)		(112,681	)		632,054
CMBS		882,762		66,416		(1,407	)		(3,618	)		944,153
CDO		798,313		8,262		(155,123	)		(4,887	)		646,565
Other asset-backed securities (2)		1,423,283		36,312		(23,474	)		(9,979	)		1,426,142
U.S. States and political subdivisions of the States		1,663,058		106,968		(1,844	)		-			1,768,182
Non-U.S. Sovereign Government, Provincial, Supranational and Government-Related/Supported (1)		3,912,982		127,717		(13,336	)		-			4,027,363
Total fixed maturities - AFS	$	26,695,459	$	1,201,055	$	(430,805	)	$	(174,047	)	$	27,291,662
Total short-term investments (1)	$	212,393	$	263	$	(329	)	$	-		$	212,327
Total equity securities	$	593,168	$	44,609	$	(6,709	)	$	-		$	631,068
Total investments - AFS	$	27,501,020	$	1,245,927	$	(437,843	)	$	(174,047	)	$	28,135,057
Fixed maturities - HTM
U.S. Government and Government-Related/Supported (1)	$	10,683	$	1,174	$	-		$	-		$	11,857
Corporate (2)		1,374,617		94,905		(4,164	)		-			1,465,358
RMBS – Non-Agency		83,023		4,259		(147	)		-			87,135
CMBS		12,912		1,211		-			-			14,123
Other asset-backed securities (2)		222,157		14,004		(573	)		-			235,588
Non-U.S. Sovereign Government, Provincial, Supranational and Government-Related/Supported (1)		1,066,408		118,273		(4,313	)		-			1,180,368
Total investments - HTM	$	2,769,800	$	233,826	$	(9,197	)	$	-		$	2,994,429

			Included in AOCI
					Gross Unrealized Losses
December 31, 2011 (U.S. dollars in thousands)	Cost or Amortized Cost		Gross Unrealized Gains		Related to Changes in Estimated Fair Value			Non-credit Related OTTI			Fair Value
Fixed maturities - AFS
U.S. Government and Government-Related/Supported (1)	$	1,864,354	$	130,874	$	(4,245	)	$	-		$	1,990,983
Corporate (2) (3) (4)		9,866,677		527,192		(233,581	)		(51,666	)		10,108,622
RMBS – Agency		5,189,473		193,782		(3,849	)		-			5,379,406
RMBS – Non-Agency		851,557		19,667		(112,867	)		(116,542	)		641,815
CMBS		927,684		56,704		(2,405	)		(7,148	)		974,835
CDO		843,553		6,624		(186,578	)		(4,997	)		658,602
Other asset-backed securities (2)		1,341,309		30,731		(25,486	)		(6,305	)		1,340,249
U.S. States and political subdivisions of the States		1,698,573		101,025		(2,220	)		-			1,797,378
Non-U.S. Sovereign Government, Provincial, Supranational and Government-Related/Supported (1)		3,188,535		127,439		(17,839	)		-			3,298,135
Total fixed maturities - AFS	$	25,771,715	$	1,194,038	$	(589,070	)	$	(186,658	)	$	26,190,025
Total short-term investments (1)	$	359,378	$	519	$	(834	)	$	-		$	359,063
Total equity securities	$	480,685	$	27,947	$	(40,435	)	$	-		$	468,197
Total investments - AFS	$	26,611,778	$	1,222,504	$	(630,339	)	$	(186,658	)	$	27,017,285
Fixed maturities - HTM
U.S. Government and Government-Related/Supported (2)	$	10,399	$	1,510	$	-		$	-		$	11,909
Corporate (2)		1,290,209		91,313		(14,433	)		-			1,367,089
RMBS – Non-Agency		80,955		6,520		(32	)		-			87,443
Other asset-backed securities (2)		288,741		20,875		(320	)		-			309,296
Non-U.S. Sovereign Government, Provincial, Supranational and Government-Related/Supported (1)		998,674		127,227		(5,950	)		-			1,119,951
Total investments - HTM	$	2,668,978	$	247,445	$	(20,735	)	$	-		$	2,895,688

Contractual MaturitiesOf Available For Sale Securities And Held To Maturity Income Securities [Table Text Block]

	March 31, 2012 (1)				December 31, 2011 (1)
(U.S. dollars in thousands)	Amortized Cost		Fair Value		Amortized Cost		Fair Value
Fixed maturities - AFS
Due less than one year	$	1,888,009	$	1,902,217	$	2,004,395	$	2,020,361
Due after 1 through 5 years		8,510,647		8,768,164		7,736,717		7,909,354
Due after 5 through 10 years		3,745,093		3,930,750		3,619,141		3,777,073
Due after 10 years		3,416,477		3,648,226		3,257,886		3,488,330
	$	17,560,226	$	18,249,357	$	16,618,139	$	17,195,118
RMBS – Agency		5,238,075		5,393,391		5,189,473		5,379,406
RMBS – Non-Agency		792,800		632,054		851,557		641,815
CMBS		882,762		944,153		927,684		974,835
CDO		798,313		646,565		843,553		658,602
Other asset-backed securities		1,423,283		1,426,142		1,341,309		1,340,249
Total mortgage and asset-backed securities	$	9,135,233	$	9,042,305	$	9,153,576	$	8,994,907
Total fixed maturities - AFS	$	26,695,459	$	27,291,662	$	25,771,715	$	26,190,025
Fixed maturities - HTM
Due less than one year	$	35,696	$	35,831	$	11,796	$	11,768
Due after 1 through 5 years		134,543		138,274		122,091		123,871
Due after 5 through 10 years		398,290		418,132		393,865		402,424
Due after 10 years		1,883,179		2,065,346		1,771,530		1,960,886
	$	2,451,708	$	2,657,583	$	2,299,282	$	2,498,949
RMBS – Non-Agency		83,023		87,135		80,955		87,443
CMBS		12,912		14,123		-		-
Other asset-backed securities		222,157		235,588		288,741		309,296
Total mortgage and asset-backed securities	$	318,092	$	336,846	$	369,696	$	396,739
Total fixed maturities - HTM	$	2,769,800	$	2,994,429	$	2,668,978	$	2,895,688

Available For Sale Securities Continuous Unrealised Loss Position [Text Block]

	Less than 12 months					Equal to or greater than 12 months
March 31, 2012 (U.S. dollars in thousands)	Fair Value		Gross Unrealized Losses			Fair Value		Gross Unrealized Losses
Fixed maturities and short-term investments - AFS
U.S. Government and Government-Related/Supported	$	478,076	$	(3,042	)	$	31,499	$	(4,183	)
Corporate (1) (2) (3)		638,803		(14,193	)		1,084,471		(177,433	)
RMBS – Agency		1,081,932		(5,053	)		34,328		(3,630	)
RMBS – Non-Agency		36,572		(3,466	)		489,071		(180,507	)
CMBS		41,017		(618	)		32,415		(4,407	)
CDO		13,501		(2,643	)		622,684		(157,367	)
Other asset-backed securities (3)		145,767		(3,683	)		163,694		(29,770	)
U.S. States and political subdivisions of the States		8,475		(40	)		16,045		(1,804	)
Non-U.S. Sovereign Government, Provincial, Supranational and Government-Related		572,425		(5,802	)		166,060		(7,540	)
Total fixed maturities and short-term investments - AFS	$	3,016,568	$	(38,540	)	$	2,640,267	$	(566,641	)
Total equity securities (4)	$	228,847	$	(6,709	)	$	-	$	-
Fixed maturities -HTM
Corporate (3)	$	61,497	$	(2,652	)	$	54,404	$	(1,512	)
RMBS – Non-Agency		9,521		(147	)		-		-
Other asset-backed securities (3)		7,709		(573	)		-		-
Non-U.S. Sovereign Government, Provincial, Supranational and Government-Related		74,668		(655	)		20,064		(3,658	)
Total fixed maturities - HTM	$	153,395	$	(4,027	)	$	74,468	$	(5,170	)

	Less than 12 months					Equal to or greater than 12 months
December 31, 2011 (U.S. dollars in thousands)	Fair Value		Gross Unrealized Losses			Fair Value		Gross Unrealized Losses
Fixed maturities and short-term investments - AFS
U.S. Government and Government-Related/Supported	$	289,260	$	(332	)	$	43,622	$	(3,984	)
Corporate (1) (2) (3)		1,078,664		(42,151	)		1,185,535		(243,683	)
RMBS – Agency		310,318		(849	)		36,960		(3,000	)
RMBS – Non-Agency		106,294		(31,714	)		449,138		(197,695	)
CMBS		69,109		(2,716	)		39,444		(6,837	)
CDO		3,357		(2,261	)		636,362		(189,456	)
Other asset-backed securities (3)		227,098		(3,324	)		161,312		(28,467	)
U.S. States and political subdivisions of the States		25,309		(199	)		27,646		(2,021	)
Non-U.S. Sovereign Government, Provincial, Supranational and Government-Related		265,766		(4,707	)		202,890		(13,166	)
Total fixed maturities and short-term investments - AFS	$	2,375,175	$	(88,253	)	$	2,782,909	$	(688,309	)
Total equity securities (4)	$	361,585	$	(40,435	)	$	-	$	-
Fixed maturities -HTM
Corporate (3)	$	147,836	$	(7,770	)	$	62,343	$	(6,663	)
RMBS – Non-Agency		9,372		(32	)		-		-
Other asset-backed securities (3)		7,743		(314	)		1,106		(6	)
Non-U.S. Sovereign Government, Provincial, Supranational and Government-Related		79,242		(1,206	)		18,330		(4,744	)
Total fixed maturities - HTM	$	244,193	$	(9,322	)	$	81,779	$	(11,413	)

Gain (Loss) on Investments [Table Text Block]

Net Realized Gains (Losses) on Investments (U.S. dollars in thousands)	Three Months Ended March 31,
	2012			2011
Gross realized gains	$	66,889		$	27,142
Gross realized losses on investments sold		(25,121	)		(56,134	)
OTTI on investments, net of amounts transferred to other comprehensive income		(20,965	)		(37,445	)
Net realized gains (losses) on investments	$	20,803		$	(66,437	)

Other than Temporary Impairment, Credit Losses Recognized in Earnings [Table Text Block]

Credit Loss Impairments (U.S. dollars in thousands)	Three Months Ended March 31,
	2012			2011
Balance at January 1,	$	333,379		$	426,372
Credit loss impairment recognized in the current period on securities not previously impaired		1,835			4,573
Credit loss impairments previously recognized on securities which matured, paid down, prepaid or were sold during the period		(18,940	)		(125,711	)
Credit loss impairments previously recognized on securities impaired to fair value during the period		(16,384	)		-
Additional credit loss impairments recognized in the current period on securities previously impaired		14,930			25,459
Accretion of credit loss impairments previously recognized due to an increase in cash flows expected to be collected		(15	)		(523	)
Balance at March 31,	$	314,805		$	330,170

Project Finance Loans (U.S. dollars in thousands)	March 31, 2012			December 31, 2011
Aggregate loan value	$	39,786		$	49,650
Aggregate loan net carrying value	$	33,886		$	40,483
Opening allowance for loan losses	$	(9,167	)	$	(9,167	)
Amounts charged off during the period		3,267			-
Closing allowance for loan losses	$	(5,900	)	$	(9,167	)
Number of individual loan participations		5			6
Number of individual loan participations relating to the allowance for loan losses		2			2
Weighted average contractual term to maturity	1.41 years			2.12 years
Weighted average credit rating	BB			BB-
Range of individual credit ratings	BB+ to B+			BB+ to CCC