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Represents the inception-to-date gains (losses) from issuances of treasury shares.

+ References

No definition available.

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- Definition

Foreign exchange rate used to translate amounts denominated in functional currency to reporting currency.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 830

-SubTopic 30

-Section S99

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6897108&loc=SL6897125-166521

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- Definition

Funds held by the ceding insurer on behalf the reinsurer, including funds held in trust, under reinsurance treaties or contracts with the assuming insurer as security for the payment of the obligations thereunder, which represent an asset for the reinsurer. There is another concept for the corresponding liability of the ceding insurer.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.2,10)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2003/role/presentationRef

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-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 2, 10

-Article 7

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- Definition

Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which is directly or indirectly attributable to that ownership interest in subsidiary equity which is not attributable to the parent (that is, noncontrolling interest, previously referred to as minority interest).

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

-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

-Number 51

-Paragraph 26

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Name Accounting Standards Codification

-Topic 210

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-Name Accounting Research Bulletin (ARB)

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-Paragraph A3

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-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 20

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Net Increase or Decrease in balance of noncontrolling interest in the subsidiary during the reporting period.

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

-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

-Number 51

-Paragraph 38

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Name Accounting Standards Codification

-Topic 810

-SubTopic 10

-Section 45

-Paragraph 16

-URI http://asc.fasb.org/extlink&oid=7656940&loc=SL4568740-111683

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- Definition

Amount of Net Income (Loss) attributable to noncontrolling interest.

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-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

-Number 51

-Paragraph 38

-Subparagraph a

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-SubTopic 10

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Basis of Presentation and Summary of Significant Accounting Policies (Details 2) (USD $) In Millions, unless otherwise specified	3 Months Ended	6 Months Ended
	Jun. 30, 2013	Jun. 30, 2013	Dec. 31, 2012	Jun. 30, 2013 British Pound (GBP)	Dec. 31, 2012 British Pound (GBP)	Jun. 30, 2012 British Pound (GBP)	Dec. 31, 2011 British Pound (GBP)	Jun. 30, 2013 Swiss Franc (CHF)	Dec. 31, 2012 Swiss Franc (CHF)	Jun. 30, 2012 Swiss Franc (CHF)	Dec. 31, 2011 Swiss Franc (CHF)
Common Shares Held in Treasury
Inception-to-date gains (losses) from issuances of treasury shares	$ 0.1	$ 0.1	$ 0.6
Funds Withheld
Funds withheld by reinsured companies	3.1	3.1	4.1
Movements in the non-controlling interest balance
Non-controlling interest - beginning	32.6
Amounts invested into the BCGR Cell on behalf of third parties	66.0	97.4
Income attributable to non-controlling interest	0.7	1.9
Non-controlling interest - ending	$ 99.3	$ 99.3
Foreign Currency Exchange
Opening Rate				1.5212	1.6234	1.5570	1.5617	1.0583	1.0924	1.0546	1.0634
Closing Rate				1.5212	1.6234	1.5570	1.5617	1.0583	1.0924	1.0546	1.0634