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Debt - Schedule of Convertible Securities (Details) - Junior Convertible Trust Preferred Securities - Junior convertible securities - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Debt Instrument [Line Items]
Contractual interest expense	$ 4.4	$ 4.5	$ 8.8	$ 9.5
Amortization of debt issuance costs	0.1	0.1	0.1	0.1
Total	$ 4.5	$ 4.6	$ 8.9	$ 9.6
Effective interest rate	5.21%	5.20%	5.21%	5.21%

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