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Related Party Transactions (Details) $ in Millions	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)
Related Party Transactions
Common stock, voting rights, percent	0.05
Other liabilities	$ 402.4	$ 466.3
Other assets	288.7	243.9
Related Party
Related Party Transactions
Other liabilities	54.8	53.9
Other assets	7.9	5.9
Related Party | Private Equity Investment Partnerships of Affiliate
Related Party Transactions
Other liabilities	14.5	$ 18.5
Related Party | Affiliate Tax Distributions
Related Party Transactions
Other liabilities	87.8
Other assets	$ 59.2

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