Investments in Affiliates and Affiliate Sponsored Investment Products - Affiliated Accounted For Under Equity Method (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Variable Interest Entity [Line Items]
Carrying value of equity method investment in affiliate	$ 2,246.6	$ 2,288.5
Carrying amount and maximum exposure to loss equity method investments considered VREs	111.4	90.3
Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity [Line Items]
Unconsolidated VIE Net Assets	1,820.4	1,492.4
Carrying Value and Maximum Exposure to Loss	$ 2,135.2	$ 2,198.2

Amount of net assets (liabilities).

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Difference between the carrying amount of assets and liabilities in the reporting entity's statement of financial position that relate to the reporting entity's variable interest in the variable interest entity (VIE) and the reporting entity's maximum exposure to loss as a result of its involvement with the VIE, where the reporting entity is not the VIE's primary beneficiary.

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