Third Party Reinsurance (Sirius Group) (Details) - USD ($) $ in Millions	Jun. 30, 2015	Dec. 31, 2014
Reinsurance Retention Policy [Line Items]
Reinsurance recoverable on paid losses	$ 31.7	$ 23.6
Reinsurance recoverable on unpaid losses	427.5	483.9
Sirius Group
Reinsurance Retention Policy [Line Items]
Reinsurance recoverable on paid losses	10.8	11.4
Reinsurance recoverable on unpaid losses	$ 280.3	$ 322.2

Amount after valuation allowance of reinsurance recoverables on paid losses.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 310

-Section 45

-Paragraph 6

-URI http://asc.fasb.org/extlink&oid=6485522&loc=d3e21412-158489

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- Definition

Amount after valuation allowance of reinsurance recoverables for losses reported to the ceding insurer but not yet paid, amounts expected of incurred losses and settlement expenses, which have not yet been reported to the ceding insurer.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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