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Redeemable Non-Controlling Interests (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Redeemable Noncontrolling Interest [Roll Forward]
Balance, beginning balance			$ 671.5
Decrease attributable to consolidated Affiliate sponsored investment products			(17.1)
Transfers to Other liabilities			(86.3)
Transfers from Non-controlling interests	$ 0.1	$ 0.2	3.9	$ 5.6
Changes in redemption value	(0.9)	$ 50.7	176.9	$ 18.6
Balance, ending balance	748.9		$ 748.9
Minimum
Noncontrolling Interest [Line Items]
Term of conditional right to put interest			5 years
Maximum
Noncontrolling Interest [Line Items]
Term of conditional right to put interest			15 years
Variable Interest Entity, Primary Beneficiary
Redeemable Noncontrolling Interest [Roll Forward]
Balance, beginning balance			$ 35.4
Balance, ending balance	$ 18.3		$ 18.3

X

- Definition

Noncontrolling Interest, Decrease from Transfers to Noncontrolling Interest Holders

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- Definition

Noncontrolling Interest, Decrease from Transfers to Other Liabilities

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Noncontrolling Interest, Increase (decrease) Attributable to Consolidated Partnerships

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- Definition

Increase (decrease) in redeemable non-controlling interests during the period as a result of a change in the redemption value.

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-- None. No documentation exists for this element. --

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- Definition

Term Of Conditional Right to Put Interest

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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.

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- Definition

As of the reporting date, the aggregate carrying amount of all noncontrolling interests which are redeemable by the (parent) entity (1) at a fixed or determinable price on a fixed or determinable date, (2) at the option of the holder of the noncontrolling interest, or (3) upon occurrence of an event that is not solely within the control of the (parent) entity. This item includes noncontrolling interest holder's ownership (or holders' ownership) regardless of the type of equity interest (common, preferred, other) including all potential organizational (legal) forms of the investee entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 480
-SubTopic 10
-Section S99
-Paragraph 3A
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