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Debt - Summary of Debt Obligations (Details) - USD ($) $ in Millions | Mar. 31, 2023 | Dec. 31, 2022
--- | --- | ---
Debt Instrument [Line Items] |  |
Long-term debt, carrying value | $ 663.2 | $ 662.8
Senior Notes | 5.25% Senior Notes Due 2028 |  |
Debt Instrument [Line Items] |  |
Long-term debt, carrying value | $ 642.1 | 641.7
Stated interest rate | 5.25% |
Debt instrument, face amount | $ 650.0 |
9% Convertible Junior Subordinated Debentures |  |
Debt Instrument [Line Items] |  |
Long-term debt, carrying value | $ 21.1 | $ 21.1
Stated interest rate | 9.00% |

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