Long-term Debt - Schedule of Long-term Debt Maturity (Details) $ in Millions	Dec. 31, 2024 USD ($)
Junior subordinated debentures
Debt Instrument [Line Items]
Total	$ 504.9
2025	22.8
2026	22.8
2027	22.8
2028	22.8
2029	22.8
Thereafter	390.9
Senior unsecured fixed rate notes
Debt Instrument [Line Items]
Total	307.2
2025	9.3
2026	9.3
2027	9.3
2028	9.3
2029	9.3
Thereafter	$ 260.7

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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