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Debt - Summary of Debt Outstanding (Details) € in Millions, $ in Millions | Mar. 31, 2023 USD ($) | Mar. 31, 2023 EUR (€) | Dec. 31, 2022 USD ($) | Mar. 31, 2022 USD ($) | Dec. 31, 2021 USD ($)
--- | --- | --- | --- | --- | ---
Debt Instrument |  |  |  |  |
Total debt | $ 556.3 |  | $ 575.2 |  |
Ark Subordinated Debt |  |  |  |  |
Debt Instrument |  |  |  |  |
Unamortized issuance cost | (4.5) |  | (4.6) |  |
Ark 2007 Subordinated Notes, carrying value | Ark Subordinated Debt |  |  |  |  |
Debt Instrument |  |  |  |  |
Amount borrowed | 30.0 |  | 30.0 |  |
Ark 2021 Subordinated Notes Tranche 1 |  |  |  |  |
Debt Instrument |  |  |  |  |
Amount borrowed | € |  | € 39.1 |  |  |
Ark 2021 Subordinated Notes Tranche 1 | Ark Subordinated Debt |  |  |  |  |
Debt Instrument |  |  |  |  |
Amount borrowed | 42.0 |  | 41.3 |  |
Ark 2021 Subordinated Notes Tranche 2 | Ark Subordinated Debt |  |  |  |  |
Debt Instrument |  |  |  |  |
Amount borrowed | 47.0 |  | 47.0 |  |
Ark 2021 Subordinated Notes Tranche 3 | Ark Subordinated Debt |  |  |  |  |
Debt Instrument |  |  |  |  |
Amount borrowed | 70.0 |  | 70.0 |  |
Ark 2021 Notes | Ark Subordinated Debt |  |  |  |  |
Debt Instrument |  |  |  |  |
Total debt | $ 154.5 |  | $ 153.7 |  |
Ark |  |  |  |  |
Debt Instrument |  |  |  |  |
Effective percentage | 10.30% | 10.30% | 7.60% |  |
Ark | Ark Subordinated Debt |  |  |  |  |
Debt Instrument |  |  |  |  |
Total debt | $ 184.5 |  | $ 183.7 |  |
Kudu Credit Facility | Asset Management (Kudu) |  |  |  |  |
Debt Instrument |  |  |  |  |
Total debt | 191.6 |  | 208.3 |  |
Other Debt | Other |  |  |  |  |
Debt Instrument |  |  |  |  |
Total debt | $ 33.6 |  | $ 36.7 |  |
HG Senior Notes |  |  |  |  |
Debt Instrument |  |  |  |  |
Effective percentage | 11.00% | 11.00% | 8.90% |  |
Secured Debt | HG Senior Notes |  |  |  |  |
Debt Instrument |  |  |  |  |
Amount borrowed | $ 150.0 |  | $ 150.0 |  |
Unamortized issuance cost | (3.4) |  | (3.5) |  |
Total debt | 146.6 |  | 146.5 |  |
Term Loan | Kudu Credit Facility |  |  |  |  |
Debt Instrument |  |  |  |  |
Amount borrowed | 198.3 |  | 215.2 |  |
Unamortized issuance cost | $ (6.7) |  | $ (6.9) |  |
Effective percentage | 8.70% | 8.70% | 6.10% |  |
Term Loan | Kudu Credit Facility | Asset Management (Kudu) |  |  |  |  |
Debt Instrument |  |  |  |  |
Total debt | $ 198.3 |  | $ 215.2 | $ 225.4 | $ 225.4
Term Loan | Other Operations |  |  |  |  |
Debt Instrument |  |  |  |  |
Amount borrowed | 34.3 |  | 37.4 |  |
Unamortized issuance cost | $ (0.7) |  | $ (0.7) |  |
Effective percentage | 8.50% | 8.50% | 6.60% |  |

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