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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 323
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
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-Publisher FASB
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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 280
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
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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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Topic 944
-SubTopic 470
-Section 45
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-Publisher FASB
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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 (Details) $ in Millions	6 Months Ended
	Jun. 30, 2023 USD ($) segment	Dec. 31, 2022	Jul. 31, 2012 USD ($)
Basis of Presentation
Number of reportable segments \| segment	3
Ark
Basis of Presentation
Percent of shares outstanding	12.50%
Ark \| Ark
Basis of Presentation
Ownership interest (as a percent)	72.00%	72.00%
Asset Management (Kudu)
Basis of Presentation
Ownership interest (as a percent)	89.20%	89.30%
Fully diluted ownership interest (as a percent)	76.10%	76.10%
Preferred Stock \| HG Global
Basis of Presentation
Ownership interest (as a percent)	96.90%	96.90%
Preferred Stock \| Outrigger Re
Basis of Presentation
Ownership interest (as a percent)	100.00%	100.00%
Common equity securities \| HG Global
Basis of Presentation
Ownership interest (as a percent)	88.40%	88.40%
HG Global
Basis of Presentation
Percentage of par value of policy reinsured	15.00%
Surplus notes \| $	$ 503.0		$ 503.0
Ark \| Ark
Basis of Presentation
Fully diluted ownership interest (as a percent)	63.00%	63.00%