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Investments in Unconsolidated Entities (Details) - White Mountains - USD ($) $ in Millions | Jun. 30, 2020 | Dec. 31, 2019
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Investments in unconsolidated affiliates |  |
Other Investments | $ 898.1 | $ 856.3
Equity method eligible private equity securities, at fair value |  |
Investments in unconsolidated affiliates |  |
Other Investments | 815.3 | 761.7
Other unconsolidated investments |  |
Investments in unconsolidated affiliates |  |
Other Investments | $ 82.8 | $ 94.6

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Details
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