The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

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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.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 944
-SubTopic 470
-Section 45
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Percentage of par value of policy reinsured.

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Summary of Significant Accounting Policies (Reportable Segments and Discontinued Operations and Assets and Liabilities Held for Sale) (Details) - USD ($) $ / shares in Units, $ in Millions	Dec. 31, 2018	May 11, 2018	Dec. 31, 2017	Sep. 28, 2017	Dec. 31, 2012
Basis of Presentation
Percentage of par value of policy reinsured	15.00%		15.00%
HG Global
Basis of Presentation
Surplus notes					$ 503.0
Preferred stocks \| HG Global
Basis of Presentation
Ownership interest (as a percent)	96.90%		96.90%
Common Stock \| HG Global
Basis of Presentation
Ownership interest (as a percent)	88.40%		88.40%
Intact Financial Corporation \| OneBeacon
Basis of Presentation
Sale of Stock, price per share				$ 18.10
NSM Insurance HoldCo, LLC
Basis of Presentation
Ownership interest (as a percent)	95.50%	95.00%
Series A BAM Surplus Note \| HG Global
Basis of Presentation
Surplus notes					203.0
Series B BAM Surplus Note \| HG Global
Basis of Presentation
Surplus notes					$ 300.0