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Discontinued Operations - Surplus Note (Details) - OneBeacon - USD ($) $ in Millions	9 Months Ended	12 Months Ended
	Sep. 30, 2017	Dec. 31, 2016
Assets, fair value adjustment		$ (29.1)
Par Value
Surplus notes	$ 101.0	$ 101.0
Fair Value
Basis points		2.50%
Surplus notes		$ 71.9
Current market rates on repayments
Assets, fair value adjustment		5.1
Current market rates on repayments | Seller Priority Surplus Note
RBC Score	250.00%
Regulatory Approval
Assets, fair value adjustment		(15.6)
Liquidity Adjustment
Assets, fair value adjustment		$ (18.6)

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Amount of addition (reduction) to the amount at which an asset could be incurred (settled) in a current transaction between willing parties.

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- Definition

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- Definition

Financial instruments issued by insurance entities (surplus notes) that are includable in surplus for statutory accounting purposes as prescribed or permitted by state laws and regulations that are liabilities of the issuer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 470
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6486086&loc=d3e24387-158525

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