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Related Party Transactions (Details) $ in Millions	Sep. 30, 2023 USD ($)	Dec. 31, 2022 USD ($)
Related Party Transactions
Other liabilities	$ 482.3	$ 461.7
Common stock, voting rights, percent	0.05
Related Party
Related Party Transactions
Other liabilities	$ 45.2	24.5
Related Party | Private Equity Investment Partnerships of Affiliate
Related Party Transactions
Other liabilities	$ 18.5	$ 21.0

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