Document And Entity Information	6 Months Ended
	Jun. 30, 2012	Aug. 06, 2012
Document and Entity Information [Abstract]
Entity Registrant Name	XL GROUP PLC
Document Type	10-Q
Current Fiscal Year End Date	--12-31
Entity Common Stock, Shares Outstanding		305,705,727
Amendment Flag	false
Entity Central Index Key	0000875159
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Large Accelerated Filer
Entity Well-known Seasoned Issuer	Yes
Document Period End Date	Jun. 30, 2012
Document Fiscal Year Focus	2012
Document Fiscal Period Focus	Q2