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Basis of Presentation and Significant Accouting Policies (Basis of Presentation) (Details) - USD ($) $ in Millions	Sep. 30, 2019	Apr. 04, 2019	Apr. 03, 2019	Mar. 31, 2019	Jan. 01, 2019	Dec. 31, 2018	May 11, 2018	Jul. 31, 2012
Basis of Presentation
Ownership interest (as a percent)	50.00%					50.00%
ROU lease asset	$ 23.0
Operating lease liability	$ 23.3
HG Global
Basis of Presentation
Percentage of par value of policy reinsured	15.00%
Surplus notes	$ 481.3							$ 503.0
Preferred Stock | 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%
NSM Insurance HoldCo, LLC
Basis of Presentation
Ownership interest (as a percent)	96.40%					95.50%	95.00%
Fully diluted ownership interest (as a percent)	88.40%					85.00%
Kudu Investment Management, LLC
Basis of Presentation
Ownership interest (as a percent)		99.10%	49.50%	49.50%		49.50%
Fully diluted ownership interest (as a percent)		85.40%	42.70%	42.70%		42.70%
Accounting Standards Update 2016-02
Basis of Presentation
ROU lease asset	$ 23.0				$ 23.2
Operating lease liability	$ 23.3				$ 23.2

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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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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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