Subsequent Events Subsequent events (Details) (Subsequent Event [Member], USD $) In Millions, except Share data, unless otherwise specified	0 Months Ended	3 Months Ended
Jan. 25, 2015	Mar. 31, 2015
Subsequent Event [Line Items]
Subsequent Event, Date	Jan. 25, 2015
PartnerRe Ltd. [Member]
Subsequent Event [Line Items]
Combined Company Shareholding Percentage	51.60%
Share Exchange Ratio Upon Amalgamation	2.18
Additional pre-tax charge on Amalgamation		$ 22
Axis Capital Holdings Ltd [Member]
Subsequent Event [Line Items]
Combined Company Shareholding Percentage	48.40%
Share Exchange Ratio Upon Amalgamation	1.00

Approximate percentage of the combined company to be owned by each of the merging entities.

No definition available.

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- Definition

Number of shares of the combined company that the merging company's shareholders will receive for every share they currently hold upon closing of the amalgamation.

+ References

No definition available.

+ Details

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- Definition

The aggregate amount of expenditures for salaries, wages, profit sharing and incentive compensation, and other employee benefits, including equity-based compensation, and pension and other postretirement benefit expense.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.4)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

+ Details

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- Details

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- Definition

Date the event occurred after the balance sheet date but before financial statements are issues or available to be issued, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 855

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6842918&loc=SL6314017-165662

+ Details

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