Acquisition and Disposals - Acquisition Consideration (Details) (Subsequent Event, Catlin Group Limited) In Thousands, except Share data, unless otherwise specified	0 Months Ended
May 01, 2015 USD ($)	May 01, 2015 GBP (£)
Business Acquisition [Line Items]
Shares outstanding (including dilutive effects of warrants) that will receive cash and share consideration	384,118,000	384,118,000
Exchange ratio per the merger agreement	0.13	0.13
Share issuance to Catlin shareholders	49,935,000	49,935,000
Share Price	$ 37.08
Share issuance consideration	$ 1,851,601
Cash price component, per share in GBP		£ 3.88
Foreign exchange rate: GBP/USD	1.5349	1.5349
Cash consideration	2,287,579	1,490,377
Total acquisition consideration	$ 4,139,180

Number of shares of equity interests issued or issuable to acquire entity.

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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Price of a single share of a number of saleable stocks of a company.

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The cash component per share paid for each outstanding share of the acquiree's common stock.

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The ratio used to calculate the number of shares of XL Group plc offered in exchange for each share of the acquiree as part of the Acquisition.

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The foreign exchange rate used to remeasure amounts denominated in a currency other than the reporting currency into the reporting currency.

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Outstanding Shares Acquired in Business Acquisition

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