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Business Combinations - Narrative, PRA Acquisition (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Business Acquisition [Line Items] |  |  |
Interest expense | $ 237,237 | $ 336,699 | $ 229,731
PRA Health Sciences, Inc |  |  |
Business Acquisition [Line Items] |  |  |
Interest expense | $ 23,500 | $ 16,400 | $ 17,700

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