Schedule II - Condensed Financial Information of Registrant - Statement of Cash Flows (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Condensed Financial Statements Captions [Line Items]
Net income (loss) attributable to ordinary shareholders	$ 1,059,916	$ 651,128	$ (474,760)
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Share based compensation	46,489	47,472	41,225
Other	9,702	(58,249)	(51,970)
Total adjustments	(356,670)	325,723	731,085
Net cash provided by (used in) operating activities	779,977	1,056,106	327,202
Cash flows provided by (used in) investing activities: [Abstract]
Net cash provided by (used in) investing activities	(1,197,862)	(942,593)	832,103
Cash flows provided by (used in) financing activities:
Proceeds from issuance of ordinary shares and exercise of stock options	12,623	5,413	576,333
Dividends paid	(160,155)	(134,799)	(138,050)
Buybacks of ordinary shares	(675,617)	(402,930)	(667,022)
Net cash provided by (used in) financing activities	(394,843)	(1,344,753)	(358,716)
Net change in cash and cash equivalents	(817,546)	(1,206,747)	802,257
Cash and cash equivalents – beginning of period	2,618,378	3,825,125	3,022,868
Cash and cash equivalents – end of period	1,800,832	2,618,378	3,825,125
XL Group PLC
Condensed Financial Statements Captions [Line Items]
Net income (loss) attributable to ordinary shareholders	1,059,916	651,128	(474,760)
Adjustments to reconcile net income (loss) to net cash provided by (used in) operating activities:
Equity in (earnings) loss of subsidiaries	(1,071,836)	(662,274)	400,612
Share based compensation	46,489	47,472	41,225
Amount due to (from) subsidiaries	104,590	166,853	(205,893)
Dividends received from subsidiaries	617,719	0	183,029
Other	(16,570)	(3,296)	10,956
Total adjustments	(319,608)	(451,245)	429,929
Net cash provided by (used in) operating activities	740,308	199,883	(44,831)
Cash flows provided by (used in) investing activities: [Abstract]
Returns of capital from subsidiaries	84,589	341,750	272,398
Net cash provided by (used in) investing activities	84,589	341,750	272,398
Cash flows provided by (used in) financing activities:
Proceeds from issuance of ordinary shares and exercise of stock options	12,623	5,413	576,333
Dividends paid	(160,155)	(134,799)	(138,050)
Buybacks of ordinary shares	(675,617)	(402,930)	(667,022)
Net cash provided by (used in) financing activities	(823,149)	(532,316)	(228,739)
Net change in cash and cash equivalents	1,748	9,317	(1,172)
Cash and cash equivalents – beginning of period	10,961	1,644	2,816
Cash and cash equivalents – end of period	$ 12,709	$ 10,961	$ 1,644