CONSOLIDATED BALANCE SHEETS (USD $) In Thousands, unless otherwise specified	Dec. 31, 2012	Dec. 31, 2011
Investments:
Fixed maturities, at fair value (amortized cost: 2012, $26,544,806; 2011, $25,771,715)	$ 27,846,920	$ 26,190,025
Equity securities, at fair value (cost: 2012, $617,486; 2010, $480,685)	649,359	468,197
Short-term investments, at fair value (amortized cost: 2012, $322,563; 2011, $359,378)	322,703	359,063
Total investments available for sale	28,818,982	27,017,285
Fixed maturities, held to maturity at amortized cost (fair value: 2012, $3,262,804 ;2011, $2,895,688)	2,814,447	2,668,978
Investments in affiliates	1,126,875	1,052,729
Other investments	1,219,879	985,262
Total investments	33,980,183	31,724,254
Cash and cash equivalents	2,618,378	3,825,125
Accrued investment income	342,778	331,758
Deferred acquisition costs	675,705	647,113
Ceded unearned premiums	587,909	596,895
Premiums receivable	2,568,861	2,411,611
Reinsurance balances receivable	58,428	220,017
Unpaid losses and loss expenses recoverable	3,382,101	3,654,948
Receivable from investments sold	16,002	59,727
Goodwill and other intangible assets	408,527	407,321
Deferred tax asset	166,142	115,601
Other assets	582,765	670,895
Total assets	45,387,779	44,665,265
Liabilities:
Unpaid losses and loss expenses	20,484,121	20,613,901
Deposit liabilities	1,551,398	1,608,108
Future policy benefit reserves	4,812,045	4,845,394
Unearned premiums	3,755,920	3,555,310
Notes payable and debt	1,672,778	2,275,327
Reinsurance balances payable	143,112	90,552
Payable for investments purchased	102,112	58,494
Deferred tax liability	141,803	91,104
Other liabilities	868,093	770,945
Total liabilities	33,531,382	33,909,135
Commitments and Contingencies
Shareholders' Equity:
Ordinary shares, 999,990,000 authorized, par value $0.01; issued and outstanding: (2012, 298,681,576; 2011, 315,645,796)	2,987	3,156
Additional paid in capital	8,584,753	8,938,679
Accumulated other comprehensive income	1,520,011	583,064
Retained earnings (deficit)	402,321	(113,241)
Shareholders' equity attributable to XL Group plc	10,510,072	9,411,658
Non-controlling interest in equity of consolidated subsidiaries	1,346,325	1,344,472
Total shareholders' equity	11,856,397	10,756,130
Total liabilities and shareholders' equity	$ 45,387,779	$ 44,665,265