Acquisition and Disposals - Financial results (Details) - Catlin Group Limited $ in Thousands	5 Months Ended
Sep. 30, 2015 USD ($)
Business Combination Results of Operations [Line Items]
Total revenues	$ 1,770,886
Net income (loss)	$ 65,796

This element represents the amount of earnings or loss of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

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This element represents the amount of revenue of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

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[Line Items] for Business Combination Results of Operations [Table]

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