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Fair Value of Financial Instruments (Details) - USD ($) $ in Millions | Dec. 31, 2022 | Dec. 31, 2021
--- | --- | ---
Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt | $ 575.2 | $ 420.9
Fair value | HG Global Senior Notes |  |
Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt, fair value | 155.7 | 0.0
Fair value | Ark 2007 Notes |  |
Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt, fair value | 28.4 | 27.6
Fair value | Ark 2021 Notes |  |
Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt, fair value | 163.1 | 162.8
Fair value | Kudu Credit Facility |  |
Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt, fair value | 223.9 | 246.8
Fair value | Other Operations |  |
Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt, fair value | 38.2 | 17.7
Carrying Value | HG Global Senior Notes |  |
Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt | 146.5 | 0.0
Carrying Value | Ark 2007 Notes |  |
Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt | 30.0 | 30.0
Carrying Value | Ark 2021 Notes |  |
Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt | 153.7 | 155.9
Carrying Value | Kudu Credit Facility |  |
Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt | 208.3 | 218.2
Carrying Value | Other Operations |  |
Balance Sheet Grouping, Financial Statement Captions [Line Items] |  |
Debt | $ 36.7 | $ 16.8

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