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Present value of lessee's discounted obligation for lease payments from operating lease.

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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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Basis of Presentation and Significant Accouting Policies (Basis of Presentation) (Details) - USD ($) $ in Millions		3 Months Ended
	Apr. 04, 2019	Dec. 31, 2019	Mar. 31, 2020	Apr. 03, 2019	Jan. 01, 2019	May 11, 2018	Feb. 05, 2018	Dec. 31, 2017	Jul. 31, 2012
Basis of Presentation
Ownership interest (as a percent)		50.00%	50.00%
ROU lease asset		$ 22.6	$ 22.9
Operating lease liability		$ 22.8	$ 23.2
Payments to acquire business, net	$ 81.4
HG Global
Basis of Presentation
Percentage of par value of policy reinsured			15.00%
Surplus notes									$ 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%			95.00%
Fully diluted ownership interest (as a percent)			88.40%			83.60%
Kudu investments
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%
Unfunded Capital Commitment	$ 250.0	$ 129.0	$ 122.5	$ 250.0
Increase (Decrease) in Capital Commitment		100.0
Funded Capital Commitment		350.0
Accounting Standards Update 2016-02
Basis of Presentation
ROU lease asset		22.6	22.9		$ 23.2
Operating lease liability		22.8	$ 23.2		$ 23.2
Series A BAM Surplus Note \| HG Global
Basis of Presentation
Surplus notes								$ 203.0	203.0
Series B BAM Surplus Note \| HG Global
Basis of Presentation
Surplus notes									$ 300.0
Kudu Debt [Member] \| Delayed Draw Term Loans [Member] \| Kudu
Basis of Presentation
Total commitment under revolving credit facility		$ 125.0