Investments (Tables)

9 Months Ended

Sep. 30, 2011

Available For Sale Securities And Held-to-maturity Securities [Table Text Block]

			Included in Accumulated Other Comprehensive Income (“AOCI”)
					Gross Unrealized Losses
September 30, 2011 (U.S. dollars in thousands) (Unaudited)	Cost or Amortized Cost		Gross Unrealized Gains		Related to Changes In Estimated Fair Value			OTTI Included In Other Comprehensive Income (Loss)(1)			Fair Value
Fixed maturities – AFS
U.S. Government and Government- Related/Supported (2)	$	1,972,718	$	141,521	$	(5,398	)	$	—		$	2,108,841
Corporate (3) (4)		10,622,568		505,910		(306,574	)		(63,996	)		10,757,908
Residential mortgage-backed securities –Agency		5,385,140		214,790		(4,791	)		—			5,595,139
Residential mortgage-backed securities – Non-Agency		889,949		19,689		(113,495	)		(113,162	)		682,981
Commercial mortgage-backed securities		978,131		50,171		(4,095	)		(7,321	)		1,016,886
Collateralized debt obligations		871,407		7,380		(198,340	)		(6,872	)		673,575
Other asset-backed securities		1,082,513		20,318		(19,393	)		(6,613	)		1,076,825
U.S. States and political subdivisions of the States		1,648,706		76,982		(2,134	)		—			1,723,554
Non-U.S. Sovereign Government, Supranational and Government- Related/Supported (2)		3,299,110		105,747		(35,216	)		—			3,369,641
Total fixed maturities – AFS	$	26,750,242	$	1,142,508	$	(689,436	)	$	(197,964	)	$	27,005,350
Total short-term investments (2) (3)	$	367,878	$	191	$	(1,390	)	$	—		$	366,679
Total equity securities (5)	$	437,668	$	27,324	$	(55,829	)	$	—		$	409,163
Total investments – AFS	$	27,555,788	$	1,170,023	$	(746,655	)	$	(197,964	)	$	27,781,192
Fixed maturities – HTM
U.S. Government and Government- Related/Supported (2)	$	10,494	$	1,300	$	—		$	—		$	11,794
Corporate		1,318,854		54,862		(18,122	)		—			1,355,594
Residential mortgage-backed securities – Non-Agency		81,923		4,898		(282	)		—			86,539
Other asset-backed securities		284,095		14,447		(16	)		—			298,526
Non-U.S. Sovereign Government, Supranational and Government-Related/Supported (2)		1,030,257		120,974		(2,250	)		—			1,148,981
Total fixed maturities – HTM	$	2,725,623	$	196,481	$	(20,670	)	$	—		$	2,901,434

			Included in Accumulated Other Comprehensive Income (“AOCI”)
					Gross Unrealized Losses
December 31, 2010 (U.S. dollars in thousands) (Unaudited)	Cost or Amortized Cost		Gross Unrealized Gains		Related to Changes In Estimated Fair Value			OTTI Included In Other Comprehensive Income (Loss)(1)			Fair Value
Fixed maturities – AFS
U.S. Government and Government- Related/Supported (2)	$	2,499,079	$	102,685	$	(36,320	)	$	—		$	2,565,444
Corporate (3) (4)		10,962,804		361,154		(281,849	)		(73,138	)		10,968,971
Residential mortgage-backed securities –Agency		5,059,249		153,106		(8,644	)		—			5,203,711
Residential mortgage-backed securities – Non-Agency		1,257,474		26,361		(133,761	)		(128,251	)		1,021,823
Commercial mortgage-backed securities		1,135,075		55,852		(7,960	)		(10,460	)		1,172,507
Collateralized debt obligations		920,501		11,014		(188,563	)		(8,814	)		734,138
Other asset-backed securities		979,539		16,111		(26,954	)		(8,164	)		960,532
U.S. States and political subdivisions of the States		1,379,150		16,755		(35,449	)		—			1,360,456
Non-U.S. Sovereign Government, Supranational and Government-Related/Supported (2)		3,129,971		70,499		(45,947	)		—			3,154,523
Total fixed maturities – AFS	$	27,322,842	$	813,537	$	(765,447	)	$	(228,827	)	$	27,142,105
Total short-term investments (2) (3)	$	450,491	$	680	$	(490	)	$	—		$	450,681
Total equity securities	$	56,737	$	28,083	$	(53	)	$	—		$	84,767
Total investments – AFS	$	27,830,070	$	842,300	$	(765,990	)	$	(228,827	)	$	27,677,553
Fixed maturities – HTM
U.S. Government and Government- Related/Supported (2)	$	10,541	$	164	$	(9	)	$	—		$	10,696
Corporate		1,337,797		6,370		(16,325	)		—			1,327,842
Residential mortgage-backed securities – Non-Agency		82,763		634		(546	)		—			82,851
Other asset-backed securities		287,109		1,134		(1,410	)		—			286,833
Non-U.S. Sovereign Government, Supranational and Government-Related/Supported (2)		1,010,125		30,680		(6,401	)		—			1,034,404
Total fixed maturities – HTM	$	2,728,335	$	38,982	$	(24,691	)	$	—		$	2,742,626

Schedule Of Fixed Maturities By Contractual Maturity [Text Block]

	(Unaudited) September 30, 2011 (1)				December 31, 2010 (1)
(U.S. dollars in thousands)	Amortized Cost		Fair Value		Amortized Cost		Fair Value
Fixed maturities - AFS
Due less than one year	$	1,920,273	$	1,918,659	$	1,552,612	$	1,546,050
Due after 1 through 5 years		8,392,810		8,582,509		8,807,515		8,936,246
Due after 5 through 10 years		3,471,196		3,653,936		3,733,842		3,857,055
Due after 10 years		3,758,823		3,804,840		3,877,035		3,710,043
		17,543,102		17,959,944		17,971,004		18,049,394
Residential mortgage-backed securities – Agency		5,385,140		5,595,139		5,059,249		5,203,711
Residential mortgage-backed securities – Non-Agency		889,949		682,981		1,257,474		1,021,823
Commercial mortgage-backed securities		978,131		1,016,886		1,135,075		1,172,507
Collateralized debt obligations		871,407		673,575		920,501		734,138
Other asset-backed securities		1,082,513		1,076,825		979,539		960,532
Total mortgage and asset-backed securities		9,207,140		9,045,406		9,351,838		9,092,711
Total fixed maturities - AFS	$	26,750,242	$	27,005,350	$	27,322,842	$	27,142,105
Fixed maturities - HTM
Due less than one year	$	11,263	$	11,237	$	—	$	—
Due after 1 through 5 years		124,921		125,889		125,449		125,416
Due after 5 through 10 years		393,059		400,583		348,797		346,494
Due after 10 years		1,830,362		1,978,660		1,884,217		1,901,032
		2,359,605		2,516,369		2,358,463		2,372,942
Residential mortgage-backed securities – Non-Agency		81,923		86,539		82,763		82,851
Other asset-backed securities		284,095		298,526		287,109		286,833
Total mortgage and asset-backed securities		366,018		385,065		369,872		369,684
Total fixed maturities - HTM	$	2,725,623	$	2,901,434	$	2,728,335	$	2,742,626

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

	Less than 12 months					Equal to or greater than 12 months
September 30, 2011 (U.S. dollars in thousands) (Unaudited)	Fair Value		Gross Unrealized Losses			Fair Value		Gross Unrealized Losses (1)
Fixed maturities and short-term investments - AFS:
U.S. Government and Government-Related/Supported	$	344,783	$	(1,977	)	$	47,632	$	(4,203	)
Corporate (2) (3)		1,566,237		(71,007	)		1,307,126		(299,904	)
Residential mortgage-backed securities – Agency		267,693		(1,362	)		32,129		(3,429	)
Residential mortgage-backed securities – Non-Agency		112,395		(31,710	)		481,732		(194,947	)
Commercial mortgage-backed securities		103,931		(4,297	)		38,618		(7,119	)
Collateralized debt obligations		3,407		(2,330	)		657,586		(202,882	)
Other asset-backed securities		105,127		(2,075	)		168,434		(23,931	)
U.S. States and political subdivisions of the States		46,831		(288	)		48,906		(1,855	)
Non-U.S. Sovereign Government, Supranational and Government-Related		298,381		(5,338	)		369,254		(30,136	)
Total fixed maturities and short-term investments - AFS	$	2,848,785	$	(120,384	)	$	3,151,417	$	(768,406	)
Total equity securities (4)	$	370,535	$	(55,829	)	$	—	$	—
Fixed maturities – HTM:
U.S. Government and Government-Related/Supported	$	—	$	—		$	—	$	—
Corporate		236,991		(16,006	)		26,861		(2,116	)
Residential mortgage-backed securities – Non-Agency		11,411		(282	)		—		—
Other asset-backed securities		1,118		(16	)		—		—
Non-U.S. Sovereign Government, Supranational and Government-Related/Supported		22,868		(2,250	)		—		—
Total fixed maturities – HTM	$	272,388	$	(18,554	)	$	26,861	$	(2,116	)

	Less than 12 months					Equal to or greater than 12 months
December 31, 2010 (U.S. dollars in thousands)	Fair Value		Gross Unrealized Losses (1)			Fair Value		Gross Unrealized Losses (1)
Fixed maturities and short-term investments - AFS:
U.S. Government and Government-Related/Supported	$	307,082	$	(25,482	)	$	117,394	$	(10,417	)
Corporate (2) (3)		2,271,887		(80,276	)		1,627,083		(275,023	)
Residential mortgage-backed securities – Agency		280,390		(6,736	)		34,186		(1,913	)
Residential mortgage-backed securities – Non-Agency		40,052		(2,574	)		843,168		(259,715	)
Commercial mortgage-backed securities		46,419		(2,472	)		69,475		(15,967	)
Collateralized debt obligations		2,500		(51	)		715,295		(197,535	)
Other asset-backed securities		122,548		(1,619	)		226,946		(33,546	)
U.S. States and political subdivisions of the States		734,893		(30,033	)		40,907		(5,452	)
Non-U.S. Sovereign Government, Supranational and Government-Related		459,686		(5,116	)		418,322		(40,837	)
Total fixed maturities and short-term investments - AFS	$	4,265,457	$	(154,359	)	$	4,092,776	$	(840,405	)
Total equity securities	$	158	$	(53	)	$	—	$	—
Fixed maturities – HTM:
U.S. Government and Government-Related/Supported	$	1,755	$	(9	)	$	—	$	—
Corporate		764,397		(16,325	)		—		—
Residential mortgage-backed securities – Non-Agency		37,899		(546	)		—		—
Other asset-backed securities		232,673		(1,410	)		—		—
Non-U.S. Sovereign Government, Supranational and Government-Related/Supported		175,382		(6,401	)		—		—
Total fixed maturities – HTM	$	1,212,106	$	(24,691	)	$	—	$	—

Gain (Loss) on Investments [Table Text Block]

	Three Months Ended September 30,						Nine Months Ended September 30,
(U.S. dollars in thousands) (Unaudited)	2011			2010			2011			2010
Gross realized gains	$	55,625		$	55,572		$	143,804		$	118,714
Gross realized losses on investments sold		(51,164	)		(86,365	)		(150,703	)		(149,465	)
OTTI on investments, net of amounts transferred to other comprehensive income		(66,815	)		(37,962	)		(131,436	)		(135,566	)
Net realized (losses) on investments	$	(62,354	)	$	(68,755	)	$	(138,335	)	$	(166,317	)

Schedule Of Fixed Maturity Credit Losses Other Than Temporary Impairments [Text Block]

	OTTI related to Credit Losses recognized in earnings
	Three Months Ended September 30,						Nine Months Ended September 30,
(U.S. dollars in thousands) (Unaudited)	2011			2010			2011			2010
Opening balance	$	315,844		$	423,041		$	426,372		$	537,121
Credit loss impairment recognized in the current period on securities not previously impaired		10,478			5,342			26,384			24,800
Credit loss impairments previously recognized on securities that matured, paid down, prepaid or were sold during the period		(16,448	)		(36,046	)		(180,475	)		(74,024	)
Credit loss impairments previously recognized on securities impaired to fair value during the period		—			—			—			(130,891	)
Additional credit loss impairments recognized in the current period on securities previously impaired		35,574			26,280			74,372			76,498
Accretion of credit loss impairments previously recognized due to an increase in cash flows expected to be collected		(2,173	)		(6,361	)		(3,378	)		(21,248	)
Balance, September 30	$	343,275		$	412,256		$	343,275		$	412,256