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Related Party Transactions (Details) $ in Millions	Mar. 31, 2025 USD ($)	Dec. 31, 2024 USD ($)
Related Party Transactions
Common stock, voting rights, percent	0.05
Other liabilities	$ 442.1	$ 402.4
Other assets	290.3	288.7
Related Party
Related Party Transactions
Other liabilities	48.4	54.8
Other assets	8.6	7.9
Related Party | Private Equity Investment Partnerships of Affiliate
Related Party Transactions
Other liabilities	13.2	14.5
Related Party | Affiliate Tax Distributions
Related Party Transactions
Other liabilities	82.1	87.8
Other assets	$ 59.8	$ 59.2

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