Segment Information (Tables)

3 Months Ended

Mar. 31, 2012

Schedule of Segment Reporting Information, by Segment [Table Text Block]

Three Months Ended March 31, 2012 (U.S. dollars in thousands, except ratios)	Insurance			Reinsurance			Total P&C			Life Operations			Total
Gross premiums written	$	1,336,634		$	980,350		$	2,316,984		$	86,683		$	2,403,667
Net premiums written		1,036,526			926,702			1,963,228			78,496			2,041,724
Net premiums earned		934,056			423,842			1,357,898			78,520			1,436,418
Net losses and loss expenses		(631,685	)		(222,380	)		(854,065	)		(121,307	)		(975,372	)
Acquisition costs		(128,256	)		(88,244	)		(216,500	)		(7,651	)		(224,151	)
Operating expenses (1)		(185,346	)		(38,747	)		(224,093	)		(2,607	)		(226,700	)
Underwriting profit (loss)	$	(11,231	)	$	74,471		$	63,240		$	(53,045	)	$	10,195
Net investment income		-			-			172,968			75,026			247,994
Net results from structured products (2)		2,819			2,498			5,317			-			5,317
Net fee income and other (3)		(2,020	)		333			(1,687	)		48			(1,639	)
Net realized gains (losses) on investments								24,967			(4,164	)		20,803
Contribution from P&C and Life Operations							$	264,805		$	17,865		$	282,670
Corporate & other:
Net realized & unrealized gains (losses) on derivative instruments														702
Net income (loss) from investment fund affiliates and operating affiliates (4)														35,661
Exchange gains (losses)														(12,718	)
Corporate operating expenses														(44,260	)
Interest expense (5)														(27,320	)
Non-controlling interests														(36,557	)
Income tax														(21,550	)
Net income (loss) attributable to XL Group plc													$	176,628
Ratios – P&C operations: (6)
Loss and loss expense ratio		67.6	%		52.5	%		62.9	%
Underwriting expense ratio		33.6	%		29.9	%		32.4	%
Combined ratio		101.2	%		82.4	%		95.3	%

Three Months Ended March 31, 2011 (U.S. dollars in thousands, except ratios)	Insurance			Reinsurance			Total P&C			Life Operations			Total
Gross premiums written	$	1,222,349		$	876,771		$	2,099,120		$	97,659		$	2,196,779
Net premiums written		918,990			795,292			1,714,282			89,672			1,803,954
Net premiums earned		875,920			395,776			1,271,696			89,687			1,361,383
Net losses and loss expenses		(788,513	)		(420,352	)		(1,208,865	)		(133,231	)		(1,342,096	)
Acquisition costs		(107,644	)		(73,526	)		(181,170	)		(7,320	)		(188,490	)
Operating expenses (1)		(164,095	)		(45,630	)		(209,725	)		(2,166	)		(211,891	)
Underwriting profit (loss)	$	(184,332	)	$	(143,732	)	$	(328,064	)	$	(53,030	)	$	(381,094	)
Net investment income		-			-			183,565			76,976			260,541
Net results from structured products (2)		3,260			4,214			7,474			-			7,474
Net fee income and other (3)		(5,912	)		1,394			(4,518	)		41			(4,477	)
Net realized gains (losses) on investments								(26,886	)		(39,551	)		(66,437	)
Contribution from P&C and Life Operations							$	(168,429	)	$	(15,564	)	$	(183,993	)
Corporate & other:
Net realized & unrealized gains (losses) on derivative instruments														3,567
Net income (loss) from investment fund affiliates and operating affiliates (4)														40,786
Exchange gains (losses)														(9,514	)
Corporate operating expenses														(35,692	)
Interest expense (5)														(41,899	)
Non-controlling interests														(33,336	)
Income tax														32,797
Net income (loss) attributable to XL Group plc													$	(227,284	)
Ratios – P&C operations: (6)
Loss and loss expense ratio		90.0	%		106.2	%		95.1	%
Underwriting expense ratio		31.0	%		30.1	%		30.7	%
Combined ratio		121.0	%		136.3	%		125.8	%

Schedule Of Net Premiums Earned By Line Of Business [Text Block]

Three Months Ended March 31, 2012 (U.S. dollars in thousands)	Insurance		Reinsurance		Life Operations		Total
P&C Operations:
Casualty - professional lines	$	323,821	$	54,908	$	-	$	378,729
Casualty - other lines		167,357		73,238		-		240,595
Property catastrophe		-		102,925		-		102,925
Other property		133,419		135,743		-		269,162
Marine, energy, aviation and satellite		120,100		35,743		-		155,843
Other specialty lines (1)		184,034		-		-		184,034
Other (2)		5,325		21,285		-		26,610
Total P&C Operations	$	934,056	$	423,842	$	-	$	1,357,898
Life Operations:
Other Life		-		-		47,063		47,063
Annuity		-		-		31,457		31,457
Total P&C Operations	$	-	$	-	$	78,520	$	78,520
Total	$	934,056	$	423,842	$	78,520	$	1,436,418

Three Months Ended March 31, 2011 (U.S. dollars in thousands)	Insurance		Reinsurance		Life Operations		Total
P&C Operations:
Casualty - professional lines	$	315,643	$	53,718	$	-	$	369,361
Casualty - other lines		156,704		51,043		-		207,747
Property catastrophe		-		94,564		-		94,564
Other property		106,921		136,243		-		243,164
Marine, energy, aviation and satellite		125,536		38,428		-		163,964
Other specialty lines (1)		168,666		-		-		168,666
Other (2)		2,450		21,780		-		24,230
Total P&C Operations	$	875,920	$	395,776	$	-	$	1,271,696
Life Operations:
Other Life		-		-		56,764		56,764
Annuity		-		-		32,923		32,923
Total P&C Operations	$	-	$	-	$	89,687	$	89,687
Total	$	875,920	$	395,776	$	89,687	$	1,361,383