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Equity Method Eligible Investments - Carrying Value and Ownership Percentages (Details) - USD ($) $ in Millions | Dec. 31, 2024 | Dec. 31, 2023
--- | --- | ---
Kudu’s Participation Contracts |  |
Investments in and Advances to Affiliates [Line Items] |  |
Carrying Value | $ 1,008.4 | $ 890.5
Investment in MediaAlpha |  |
Investments in and Advances to Affiliates [Line Items] |  |
Ownership Interest | 26.60% | 34.90%
Carrying Value | $ 201.6 | $ 254.9
PassportCard/DavidShield |  |
Investments in and Advances to Affiliates [Line Items] |  |
Ownership Interest | 53.80% | 53.80%
Carrying Value | $ 150.0 | $ 150.0
Elementum |  |
Investments in and Advances to Affiliates [Line Items] |  |
Ownership Interest | 26.60% | 26.60%
Carrying Value | $ 35.0 | $ 35.0
Other equity method eligible investments, at fair value |  |
Investments in and Advances to Affiliates [Line Items] |  |
Carrying Value | 243.7 | 291.7
Other equity method eligible investments, at fair value |  |
Investments in and Advances to Affiliates [Line Items] |  |
Carrying Value | $ 0.0 | $ 24.8
Minimum | Kudu’s Participation Contracts |  |
Investments in and Advances to Affiliates [Line Items] |  |
Ownership Interest | 4.10% | 4.10%
Maximum | Kudu’s Participation Contracts |  |
Investments in and Advances to Affiliates [Line Items] |  |
Ownership Interest | 30.00% | 30.00%

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- Definition The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 323 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (a)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147481687/323-10-50-3 + Details
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