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Investments in Marketable Securities - Additional Information (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2019 | Dec. 31, 2018
Marketable Securities [Abstract] |  |
Proceeds from sale of investments in marketable securities | $ 38.0 | $ 81.4
Net gains on sales of marketable securities | 1.1 | 6.9
Affiliate sponsored investment products |  |
Marketable Securities [Line Items] |  |
Fair value of deconsolidated affiliate | $ 38.1 | $ 105.1

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- Definition Marketable Securities, Fair Value, Deconsolidation + References No definition available. + Details
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- 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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- 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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