Investments in Affiliates and Affiliate Sponsored Investment Products (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Variable Interest Entity [Line Items]
Equity method investments in Affiliates (net)	$ 2,870.4	$ 2,246.6
Equity method investments	106.8	111.4
Variable Interest Entity, Not Primary Beneficiary
Variable Interest Entity [Line Items]
Maximum loss exposure attributable to affiliates accounted for under equity method	2,763.6	2,135.2
Variable Interest Entity, Primary Beneficiary
Variable Interest Entity [Line Items]
Maximum loss exposure attributable to affiliate sponsored investment products	$ 88.9	$ 28.0

This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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