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Investments in Marketable Securities - Additional Information (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2020 | Sep. 30, 2019 | Sep. 30, 2020 | Sep. 30, 2019 | Dec. 31, 2019
Investments, Debt and Equity Securities [Abstract] |  |  |  |  |
Proceeds received from sales of marketable securities | $ 16.7 | $ 2.9 | $ 80.8 | $ 21.4 |
Variable Interest Entity, Primary Beneficiary |  |  |  |  |
Investments in and Advances to Affiliates [Line Items] |  |  |  |  |
Fair value of deconsolidated investment in affiliate | $ 43.4 |  | $ 43.4 |  | $ 38.1

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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 The cash inflow associated with the aggregate amount received by the entity through sale or maturity of marketable securities (held-to-maturity or available-for-sale) during the period. + References No definition available. + Details
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- Details
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