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Redeemable Non-Controlling Interests (Details) - USD ($) $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2024 | Mar. 31, 2023
Redeemable Noncontrolling Interest [Roll Forward] |  |
Balance, beginning balance | $ 393.4 |
Decrease attributable to consolidated Affiliate sponsored investment products | (8.2) |
Transfers to Other liabilities | (10.3) |
Changes in redemption value | 18.1 | $ 101.7
Balance, ending balance | $ 393.0 |
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 | $ 11.8 |
Balance, ending balance | $ 3.6 |

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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 -Name Accounting Standards Codification -Topic 480 -SubTopic 10 -Subparagraph (12)(c) -Section S99 -Paragraph 3A -Publisher FASB -URI https://asc.fasb.org//1943274/2147480244/480-10-S99-3A Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 480 -SubTopic 10 -Subparagraph 14 -Paragraph 3A -Section S99 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480244/480-10-S99-3A Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 480 -SubTopic 10 -Subparagraph 15 -Paragraph 3A -Section S99 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480244/480-10-S99-3A Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 480 -SubTopic 10 -Subparagraph (16)(c) -Paragraph 3A -Section S99 -Publisher FASB -URI https://asc.fasb.org//1943274/2147480244/480-10-S99-3A + Details
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