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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Value of the investment at close of period. For schedules of investments that are categorized, the value would be aggregated by category. For investment in and advances to affiliates, if operations of any controlled companies are different in character from those of the company, group such affiliates within divisions and by type of activities.

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Rate of interest credited to policyholder deposits.

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Maximum number of shares that may be issued in accordance with the plan as a proportion of outstanding capital stock.

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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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Investment, Fully Diluted Ownership Percentage

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Investment Owned, Increase (Decrease) In Value

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Percent of Underwriting Capital Provided by Third Parties

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Percentage of par value of policy reinsured.

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Basis of Presentation and Significant Accounting Policies (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
	Jun. 30, 2021	Sep. 30, 2021	Dec. 31, 2020	Dec. 31, 2012	Jul. 31, 2012
Ark
Basis of Presentation
Percent of shares outstanding		12.50%
Ark
Basis of Presentation
Percent of underwriting capital provided by third parties		51.00%
NSM Insurance HoldCo, LLC
Basis of Presentation
Ownership interest (as a percent)		96.60%	96.50%
Fully diluted ownership interest (as a percent)		87.30%	89.60%
Asset Management (Kudu)
Basis of Presentation
Ownership interest (as a percent)		99.30%	99.10%
Fully diluted ownership interest (as a percent)		84.70%	85.40%
HG Global
Basis of Presentation
Percentage of par value of policy reinsured		15.00%
Surplus notes				$ 503.0	$ 503.0
HG Global \| Preferred Stock
Basis of Presentation
Ownership interest (as a percent)		96.90%	96.90%
HG Global \| Common equity securities
Basis of Presentation
Ownership interest (as a percent)		88.40%	88.40%
HG Global \| Series A BAM Surplus Note
Basis of Presentation
Surplus notes					203.0
HG Global \| Series B BAM Surplus Note
Basis of Presentation
Surplus notes					$ 300.0
Ark
Basis of Presentation
Ownership interest (as a percent)		72.00%
Ark \| Ark
Basis of Presentation
Ownership interest (as a percent)		72.00%
Fully diluted ownership interest (as a percent)		63.00%
Ark \| Ark
Basis of Presentation
Fully diluted ownership interest (as a percent)		63.00%
Ark \| Third Point Re
Basis of Presentation
Annual crediting rate		3.00%
Decrease in investment	$ (31.7)
Carrying value of investment		$ 20.3