General	12 Months Ended
Dec. 31, 2015
Organization, Consolidation and Presentation of Financial Statements [Abstract]
General	General XL Group plc, an Irish public limited company ("XL-Ireland"), through its operating subsidiaries (collectively, the "Company"), is a leading provider of insurance and reinsurance coverages to industrial, commercial and professional firms, insurance companies and other enterprises on a worldwide basis. Unless the context otherwise indicates, references herein to the "Company" are to, and these financial statements include the accounts of, XL-Ireland and its consolidated subsidiaries. The Company and its various subsidiaries operate globally in 29 countries, through the Company's two business segments: Insurance and Reinsurance. These segments are further discussed in Note 5, "Segment Information." On May 1, 2015, the Company completed its acquisition (the "Catlin Acquisition") of Catlin Group Limited and its consolidated subsidiaries ("Catlin"). Catlin, through its wholly-owned subsidiaries, provided property, casualty and specialty insurance and reinsurance coverage on a worldwide basis. The Company's consolidated results of operations include those of Catlin from May 1, 2015. See Note 3(c), "Acquisitions and Disposals - Catlin Acquisition," for additional information with respect to the acquisition of Catlin. On July 1, 2010, XL-Ireland and XLIT Ltd. (formerly XL Capital Ltd.), a Cayman Islands exempted company ("XL-Cayman") completed a redomestication transaction in which all of the ordinary shares of XL-Cayman were exchanged for all of the ordinary shares of XL-Ireland (the "Redomestication"). As a result, XL-Cayman became a wholly owned subsidiary of XL-Ireland. On July 23, 2010, the Irish High Court approved XL-Ireland’s creation of distributable reserves, subject to the completion of certain formalities under Irish Company law. These formalities were completed in early August 2010.

General

12 Months Ended

Dec. 31, 2015

Organization, Consolidation and Presentation of Financial Statements [Abstract]

XL Group plc, an Irish public limited company ("XL-Ireland"), through its operating subsidiaries (collectively, the "Company"), is a leading provider of insurance and reinsurance coverages to industrial, commercial and professional firms, insurance companies and other enterprises on a worldwide basis. Unless the context otherwise indicates, references herein to the "Company" are to, and these financial statements include the accounts of, XL-Ireland and its consolidated subsidiaries. The Company and its various subsidiaries operate globally in 29 countries, through the Company's two business segments: Insurance and Reinsurance. These segments are further discussed in Note 5, "Segment Information."

On May 1, 2015, the Company completed its acquisition (the "Catlin Acquisition") of Catlin Group Limited and its consolidated subsidiaries ("Catlin"). Catlin, through its wholly-owned subsidiaries, provided property, casualty and specialty insurance and reinsurance coverage on a worldwide basis. The Company's consolidated results of operations include those of Catlin from May 1, 2015. See Note 3(c), "Acquisitions and Disposals - Catlin Acquisition," for additional information with respect to the acquisition of Catlin.

On July 1, 2010, XL-Ireland and XLIT Ltd. (formerly XL Capital Ltd.), a Cayman Islands exempted company ("XL-Cayman") completed a redomestication transaction in which all of the ordinary shares of XL-Cayman were exchanged for all of the ordinary shares of XL-Ireland (the "Redomestication"). As a result, XL-Cayman became a wholly owned subsidiary of XL-Ireland. On July 23, 2010, the Irish High Court approved XL-Ireland’s creation of distributable reserves, subject to the completion of certain formalities under Irish Company law. These formalities were completed in early August 2010.