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Investments in Marketable Securities - Additional Information (Details) - USD ($) $ in Millions	Mar. 31, 2021	Dec. 31, 2020
Variable Interest Entity, Primary Beneficiary
Investments in and Advances to Affiliates [Line Items]
Marketable securities, consolidated Affiliate sponsored investment products	$ 77.8	$ 52.3

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- Definition

Marketable Securities, Fair Value

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	instant

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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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Namespace Prefix:	us-gaap_
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Balance Type:	na
Period Type:	duration

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- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: