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Equity Incentive Schemes and Stock Compensation Charges - Summary of Stock Option Activity (Details) - Stock Option and Award Plans - $ / shares	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Options Granted Under Plans
Beginning balance (in shares)	553,746	656,107	920,746
Assumed through business combination (in shares)	2,177,130
Granted (in shares)	100,299	107,737	97,112
Exercised (in shares)	(1,065,529)	(193,417)	(329,870)
Canceled/expired (in shares)	(70,186)	(16,681)	(31,881)
Ending balance (in shares)	1,695,460	553,746	656,107
Vested and exercisable at end of period (in shares)	989,419
Weighted Average Exercise Price
Beginning balance (USD per share)	$ 108.53	$ 87.80	$ 74.32
Assumed through business combination (USD per share)	108.78
Granted (USD per share)	177.76	159.83	140.13
Exercised (USD per share)	111.29	68.19	65.54
Canceled/expired (USD per share)	128.46	92.21	88.12
Ending balance (USD per share)	104.79	$ 108.53	$ 87.80
Vested and exercisable at end of period (USD per share)	$ 91.70

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Gross number of share options (or share units) granted during the period.

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Number of options outstanding, including both vested and non-vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Number of fully vested and expected to vest exercisable options that may be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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