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Investments in Marketable Securities - Additional Information (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Variable Interest Entity, Primary Beneficiary
Investments in and Advances to Affiliates [Line Items]
Fair value of deconsolidated investment in affiliate	$ 19.0	$ 52.3

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- Definition

Marketable Securities, Fair Value, Deconsolidation

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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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- Details

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