Equity Incentive Schemes and Stock Compensation Charges - Summary of Stock Option Activity (Details) - Stock Option and Award Plans - $ / shares	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Options Granted Under Plans
Beginning balance (in shares)	902,806	1,378,119	1,695,460
Granted (in shares)	68,380	82,472	108,643
Exercised (in shares)	(311,040)	(535,705)	(348,286)
Canceled/expired (in shares)	(37,854)	(22,080)	(77,698)
Ending balance (in shares)	622,292	902,806	1,378,119
Vested and exercisable at end of period (in shares)	426,497
Weighted Average Exercise Price
Beginning balance (USD per share)	$ 142.96	$ 119.86	$ 110.38
Granted (USD per share)	325.51	232.48	229.94
Exercised (USD per share)	116.31	95.12	102.87
Canceled/expired (USD per share)	238.51	196.20	143.08
Ending balance (USD per share)	170.52	$ 142.96	$ 119.86
Vested and exercisable at end of period (USD per share)	$ 135.39

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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 718
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-URI https://asc.fasb.org/1943274/2147480429/718-10-50-2

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Weighted-average exercise price, at which grantee can acquire shares reserved for issuance, for fully vested and expected to vest exercisable or convertible options. 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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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Number of share options (or share units) exercised during the current period.

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