CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY (USD $) In Thousands	Noncontrolling Interest [Member]	Preferred Stock [Member]	Common Stock [Member] Common Class A [Member]	Additional Paid-in Capital [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Retained Earnings [Member]	Total
Balance at Dec. 31, 2009	$ 2,305	$ 10	$ 3,421	$ 10,474,688	$ (1,142,467)	$ 94,460
Impact of adoption of new authoritative embedded derivative guidance, net of tax					31,917	(31,917)
Net income (loss) attributable to XL Group plc						415,428	415,428	[1]
Dividends on preference ordinary shares						(34,694)
Dividends on ordinary shares						(102,119)
Gain on redemption of Redeemable Series C preference ordinary shares						16,616	16,616
Change in net unrealized gains (losses) on investments, net of tax					1,285,845
Change in net unrealized gains (losses) on affiliate and other investments, net of tax					25,113		25,113
Change in OTTI losses recognized in other comprehensive income, net of tax					81,102
Change in underfunded pension liability					(478)		(478)
Change in value of cash flow hedge					330		330
Foreign currency translation adjustments					(3,461)		(3,461)
Change in net unrealized gain (loss) on future policy benefit reserves					(3,714)		(3,714)
Issuance of ordinary shares				1,102
Exercise of stock options				790
Share based compensation expense				26,126
Buybacks of ordinary shares			(139)	(270,572)
Transfer to non-controlling interest in equity of consolidated subsidiaries		(10)		(999,990)
Non-controlling interests	(75)						32,425
Non-controlling interest share in change in accumulated other comprehensive (income) loss	(7)
Transfer from Series E preference ordinary shares and additional paid in capital	1,000,000
Balance at Sep. 30, 2010	1,002,223		3,282	9,232,144	274,187	357,774	10,869,610
Balance at Dec. 31, 2010	1,002,296		3,165	8,993,016	100,795	513,777	10,613,049
Net income (loss) attributable to XL Group plc						40,777	40,777	[1]
Dividends on ordinary shares						(104,020)
Change in net unrealized gains (losses) on investments, net of tax					291,330
Change in net unrealized gains (losses) on affiliate and other investments, net of tax					35,620		35,620
Change in OTTI losses recognized in other comprehensive income, net of tax					28,119
Change in underfunded pension liability					1,287		1,287
Change in value of cash flow hedge					330		330
Foreign currency translation adjustments					(1,278)		(1,278)
Issuance of ordinary shares			307	573,460
Exercise of stock options			1	1,195
Share based compensation expense				29,261
Buybacks of ordinary shares			(267)	(566,673)
Non-controlling interests	4						69,431
Non-controlling interest share in change in accumulated other comprehensive (income) loss	(16)
Purchase of Series E preference ordinary shares	(500)
Balance at Sep. 30, 2011	$ 1,001,784		$ 3,206	$ 9,030,259	$ 456,203	$ 450,534	$ 10,941,986

[1] During the first quarter of 2011, the Redeemable Series C preference ordinary shares were reclassified as Non-controlling interest - Redeemable Series C preference ordinary shares and Series E preference ordinary shares were reclassified as Non-controlling interest in equity of consolidated subsidiaries on the Company's consolidated balance sheet as a result of changes in ownership structure arising as part of the Company's redomestication of the ultimate parent holding company to Ireland as of July 1, 2010. Accordingly, preference share dividends declared are recorded as Non-controlling interests rather than as Preference share dividends within the consolidated statements of income from July 1, 2010 onwards. See Note 1, "Basis of Preparation and Consolidation" for additional details. During the third quarter of 2011, all outstanding Redeemable Series C preference ordinary shares were repurchased and canceled.