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Related Party Transactions (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Related Party |  |  |
Related Party Transaction [Line Items] |  |  |
Management fee expense | $ 1.8 | $ 1.9 | $ 2.0
Accounts payable | $ 1.0 | $ 1.0 |
Wellington Management Company LLP |  |  |
Related Party Transaction [Line Items] |  |  |
Ownership percentage by noncontrolling owners | 5.00% | 5.00% |
BlackRock Financial Management Inc. |  |  |
Related Party Transaction [Line Items] |  |  |
Ownership percentage by noncontrolling owners | 5.00% | 5.00% |

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