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Debt - Junior Convertible Securities (Details) $ / shares in Units, $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2024 USD ($) d $ / shares | Dec. 31, 2023 USD ($)
Debt Instrument [Line Items] |  |
Debt | $ 2,524.9 | $ 2,537.5
Junior convertible securities |  |
Debt Instrument [Line Items] |  |
Debt | 338.9 | 338.9
Junior Convertible Trust Preferred Securities | Junior convertible securities |  |
Debt Instrument [Line Items] |  |
Debt | $ 341.7 |
Debt interest rate | 5.15% |
Unamortized debt issuance costs | $ 2.8 | $ 2.9
Conversion ratio per share of common stock | 0.2558 |
Face amount of convertible security (in dollars per share) | $ / shares | $ 50.00 |
Adjusted conversion price (in dollars per share) | $ / shares | $ 195.47 |
Convertible debt, threshold trading days | d | 20 |
Convertible debt, threshold consecutive trading days | d | 30 |
Debt instrument, convertible, threshold percentage | 1.30 |

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