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Business combinations - Schedule of Fair Value of Intangible Assets PRA Health Sciences Inc Acquisition (Details) - PRA Health Sciences Inc $ in Thousands | Jul. 01, 2021 USD ($)
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Business Acquisition [Line Items] |
Estimated Fair Value | $ 4,875,000
Customer relationships |
Business Acquisition [Line Items] |
Estimated Fair Value | $ 3,905,000
Estimated Useful Life | 23 years
Order backlog |
Business Acquisition [Line Items] |
Estimated Fair Value | $ 489,000
Estimated Useful Life | 3 years
Trade names |
Business Acquisition [Line Items] |
Estimated Fair Value | $ 202,000
Estimated Useful Life | 3 years
Patient database |
Business Acquisition [Line Items] |
Estimated Fair Value | $ 168,000
Estimated Useful Life | 7 years
Technology assets |
Business Acquisition [Line Items] |
Estimated Fair Value | $ 111,000
Estimated Useful Life | 5 years

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