Shares Issued, Shares, Share-Based Payment Arrangement, Acquisitions

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.

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Amount of liabilities incurred by the acquirer as part of consideration transferred in a business combination.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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The cash outflow from the repayments of a long-term debt originally issued by another party but is assumed by the entity.

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Business combinations - Fair Value of PRA Health Sciences Inc Acquisition Consideration (Details) - USD ($) $ in Thousands		3 Months Ended	9 Months Ended
	Jul. 01, 2021	Sep. 30, 2021	Sep. 30, 2021	Sep. 30, 2020
Business Acquisition [Line Items]
Fair value of cash consideration			$ 5,914,475	$ 37,761
Fair value of replacement share-based awards issued to acquiree employees		$ 209,399
PRA Health Sciences Inc
Business Acquisition [Line Items]
Fair value of cash consideration	$ 5,308,646
Fair value of ordinary shares issued to acquiree stockholders	5,658,126
Fair value of replacement share-based awards issued to acquiree employees	209,399
Repayment of term loan obligations and accrued interest	865,800
Total consideration	12,041,971
Repayments of assumed debt obligtaions	$ 401,600