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Investments in Marketable Securities - Additional Information (Details) - USD ($) $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2020 | Mar. 31, 2019 | Dec. 31, 2019
Investments, Debt and Equity Securities [Abstract] |  |  |
Proceeds received from sales of marketable securities | $ 26.2 | $ 15.1 |
Net realized gains on sale of marketable securities | (1.0) | $ 0.5 |
Variable Interest Entity, Primary Beneficiary |  |  |
Investments in and Advances to Affiliates [Line Items] |  |  |
Fair value of deconsolidated investment in affiliate | $ 33.2 |  | $ 38.1

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- Definition Marketable Securities, Fair Value, Deconsolidation + References No definition available. + Details
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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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- Definition Amount of realized gain (loss) on investment in marketable security, including other-than-temporary impairment (OTTI). + References No definition available. + Details
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- Details
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