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Borrowings - Additional Information (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Debt Disclosure [Abstract] |  |  |
Interest expense | $ 38.7 | $ 44.5 |
Unused commitment fees | $ 1.2 | $ 0.8 |
Weighted average interest rate | 4.93% | 3.46% | 2.92%
Average principal debt outstanding | $ 5,275.4 | $ 5,732.6 | $ 4,000.8

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