UNAUDITED CONSOLIDATED BALANCE SHEETS (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Investments:
Fixed maturities, at fair value (amortized cost: 2015, $27,370,101; 2014, $27,728,771)	$ 29,110,400	$ 29,359,034
Equity securities, at fair value (cost: 2015, $665,682; 2014, $763,833)	783,471	868,292
Short-term investments, at fair value (amortized cost: 2015, $169,903; 2014, $257,221)	168,862	256,727
Total investments available for sale	30,062,733us-gaap_AvailableForSaleSecurities	30,484,053us-gaap_AvailableForSaleSecurities
Fixed maturities, trading at fair value (amortized cost: 2015, $138,647; 2014, $1,180)	139,377us-gaap_TradingSecuritiesDebt	1,171us-gaap_TradingSecuritiesDebt
Investments in affiliates	1,655,394us-gaap_EquityMethodInvestments	1,637,620us-gaap_EquityMethodInvestments
Other investments	1,328,935us-gaap_OtherLongTermInvestments	1,248,439us-gaap_OtherLongTermInvestments
Total investments	33,186,439us-gaap_Investments	33,371,283us-gaap_Investments
Cash and cash equivalents	3,209,934	2,521,814
Accrued investment income	278,714	315,964
Deferred acquisition costs	417,275us-gaap_DeferredPolicyAcquisitionCosts	354,533us-gaap_DeferredPolicyAcquisitionCosts
Ceded unearned premiums	1,078,575us-gaap_PrepaidReinsurancePremiums	952,525us-gaap_PrepaidReinsurancePremiums
Premiums receivable	2,898,739	2,473,736
Reinsurance balances receivable	118,384	131,519
Unpaid losses and loss expenses recoverable	3,529,331	3,429,368
Receivable from investments sold	19,627	92,762
Goodwill and other intangible assets	442,431	447,952
Deferred tax asset	192,286us-gaap_DeferredTaxAssetsNet	204,491us-gaap_DeferredTaxAssetsNet
Other assets	708,821us-gaap_OtherAssets	750,872us-gaap_OtherAssets
Total assets	46,080,556us-gaap_Assets	45,046,819us-gaap_Assets
Liabilities:
Unpaid losses and loss expenses	18,965,264	19,353,243
Deposit liabilities	1,211,203us-gaap_DepositContractsLiabilities	1,245,367us-gaap_DepositContractsLiabilities
Future policy benefit reserves	4,375,863	4,707,199
Funds withheld on life retrocession arrangements (net of future policy benefit reserves recoverable: 2015, $3,933,589; 2014, 4,265,678)	1,138,652xlgroup_FundsWithheldLiability	1,155,016xlgroup_FundsWithheldLiability
Unearned premiums	4,532,022us-gaap_UnearnedPremiums	3,973,132us-gaap_UnearnedPremiums
Notes payable and debt	2,643,561us-gaap_LongTermDebt	1,662,580us-gaap_LongTermDebt
Reinsurance balances payable	558,952us-gaap_ReinsurancePayable	493,230us-gaap_ReinsurancePayable
Payable for investments purchased	75,145us-gaap_InvestmentRelatedLiabilities	42,291us-gaap_InvestmentRelatedLiabilities
Deferred tax liability	66,115us-gaap_DeferredIncomeTaxLiabilities	66,246us-gaap_DeferredIncomeTaxLiabilities
Other liabilities	867,356us-gaap_OtherLiabilities	912,749us-gaap_OtherLiabilities
Total liabilities	34,434,133us-gaap_Liabilities	33,611,053us-gaap_Liabilities
Commitments and Contingencies
Shareholders' Equity:
Ordinary shares, 999,990,000 authorized, par value $0.01; issued and outstanding (2015, 256,683,621; 2014, 255,182,955)	2,567us-gaap_CommonStockValue	2,552us-gaap_CommonStockValue
Additional paid in capital	7,361,138	7,359,102
Accumulated other comprehensive income	1,705,170	1,484,458
Retained earnings	1,175,182	1,187,639
Shareholders' equity attributable to XL Group plc	10,244,057us-gaap_StockholdersEquity	10,033,751us-gaap_StockholdersEquity
Non-controlling interest in equity of consolidated subsidiaries	1,402,366us-gaap_MinorityInterest	1,402,015us-gaap_MinorityInterest
Total shareholders' equity	11,646,423	11,435,766
Total liabilities and shareholders' equity	$ 46,080,556	$ 45,046,819

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Amount of investments in debt securities classified as trading.

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