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Significant Transactions - Kudu (Details) $ in Millions | May 26, 2022 USD ($) | Dec. 31, 2022 | May 25, 2022 | Dec. 31, 2021 USD ($) portfolioCompany
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Other Significant Noncash Transactions [Line Items] |  |  |  |
Number of portfolio companies | portfolioCompany |  |  |  | 2
Subsidiary - Kudu Investment Management, LLC |  |  |  |
Other Significant Noncash Transactions [Line Items] |  |  |  |
Ownership percentage basic units outstanding | 89.30% | 89.30% | 99.10% |
Subsidiary - Kudu Investment Management, LLC |  |  |  |
Other Significant Noncash Transactions [Line Items] |  |  |  |
Equity capital raised | $ 114.5 |  |  |
Pre-money valuation ratio | 1.3 |  |  |
Pre-money valuation amount | $ 114.0 |  |  |
Subsidiary - Kudu Investment Management, LLC | Kudu’s Participation Contracts |  |  |  |
Other Significant Noncash Transactions [Line Items] |  |  |  |
Enterprise value excluded |  |  |  | $ 54.3
Subsidiary - Kudu Investment Management, LLC | Massachusetts Mutual Life Insurance Company |  |  |  |
Other Significant Noncash Transactions [Line Items] |  |  |  |
Equity capital raised | 64.1 |  |  |
Subsidiary - Kudu Investment Management, LLC | White Mountains |  |  |  |
Other Significant Noncash Transactions [Line Items] |  |  |  |
Equity capital raised | 50.0 |  |  |
Subsidiary - Kudu Investment Management, LLC | Kudu |  |  |  |
Other Significant Noncash Transactions [Line Items] |  |  |  |
Equity capital raised | $ 0.4 |  |  |

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