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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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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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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Equity Method Investment, Fully Diluted Ownership Percentage

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Percentage of par value of policy reinsured.

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Basis of Presentation and Significant Accounting Policies - Reportable Segments (Details) $ in Millions		12 Months Ended
	Jan. 01, 2021	Dec. 31, 2022 segment	Dec. 31, 2021	Dec. 31, 2012 USD ($)
Basis of Presentation
Number of operating segments \| segment		3
Ark
Basis of Presentation
Percent of shares outstanding	12.50%	12.50%
HG Global
Basis of Presentation
Percentage of par value of policy reinsured		15.00%
Surplus notes \| $				$ 503.0
HG Global \| Preferred stocks
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%
Ark \| Ark
Basis of Presentation
Ownership interest (as a percent)		72.00%	72.00%
Fully diluted ownership interest (as a percent)		63.00%	63.00%
NSM
Basis of Presentation
Ownership interest (as a percent)			96.50%
Fully diluted ownership interest (as a percent)			87.30%
Kudu
Basis of Presentation
Ownership interest (as a percent)		89.30%	99.30%
Fully diluted ownership interest (as a percent)		76.10%	84.70%