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Fair Value of Financial Instruments (Details) - USD ($) $ in Millions | Sep. 30, 2022 | Dec. 31, 2021
--- | --- | ---
Balance Sheet Grouping, Financial Statement Captions |  |
Carrying Value | $ 615.5 | $ 420.9
Kudu Credit Facility |  |
Balance Sheet Grouping, Financial Statement Captions |  |
Carrying Value | 253.5 | 218.2
Other Operations debt |  |
Balance Sheet Grouping, Financial Statement Captions |  |
Carrying Value | 35.6 |
Fair Value | HG Global Senior Notes |  |
Balance Sheet Grouping, Financial Statement Captions |  |
Fair Value | 146.1 | 0.0
Fair Value | Ark 2007 Notes |  |
Balance Sheet Grouping, Financial Statement Captions |  |
Fair Value | 26.2 | 27.6
Fair Value | Ark 2021 Notes |  |
Balance Sheet Grouping, Financial Statement Captions |  |
Fair Value | 149.4 | 162.8
Fair Value | Kudu Credit Facility |  |
Balance Sheet Grouping, Financial Statement Captions |  |
Fair Value | 265.5 | 246.8
Fair Value | Other Operations debt |  |
Balance Sheet Grouping, Financial Statement Captions |  |
Fair Value | 36.8 | 17.7
Carrying Value | HG Global Senior Notes |  |
Balance Sheet Grouping, Financial Statement Captions |  |
Carrying Value | 146.4 | 0.0
Carrying Value | Ark 2007 Notes |  |
Balance Sheet Grouping, Financial Statement Captions |  |
Carrying Value | 30.0 | 30.0
Carrying Value | Ark 2021 Notes |  |
Balance Sheet Grouping, Financial Statement Captions |  |
Carrying Value | 150.0 | 155.9
Carrying Value | Kudu Credit Facility |  |
Balance Sheet Grouping, Financial Statement Captions |  |
Carrying Value | 260.4 | 218.2
Carrying Value | Other Operations debt |  |
Balance Sheet Grouping, Financial Statement Captions |  |
Carrying Value | $ 35.6 | $ 16.8

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