STOCK-BASED COMPENSATION - Stock option grants (Details) - $ / shares	6 Months Ended
Jun. 30, 2024	Jun. 30, 2023
Share-Based Compensation Awards
Weighted average grant-date fair value of stock options granted (in dollars per share)	$ 8.36	$ 3.65
Granted (in shares)	1,812,760
New non-executive director
Share-Based Compensation Awards
Granted (in shares)	27,900
Non-executive directors, excluding new non-executive director
Share-Based Compensation Awards
Granted (in shares)	87,270
Employees excluding non-executive directors
Share-Based Compensation Awards
Granted (in shares)	1,697,590
Employee Stock Option
Share-Based Compensation Awards
Expected term (in years)	6 years 2 months 12 days	6 years 2 months 12 days
Risk-free interest rate (as a percent)	4.20%	3.60%
Employee Stock Option \| Maximum
Share-Based Compensation Awards
Term of award	10 years
Employee Stock Option \| New non-executive director
Share-Based Compensation Awards
Vesting period	3 years
Employee Stock Option \| Non-executive directors
Share-Based Compensation Awards
Vesting period	1 year
Employee Stock Option \| Tranche one \| Employees excluding non-executive directors
Share-Based Compensation Awards
Vesting period	1 year
Vesting (as a percent)	25.00%
Employee Stock Option \| Tranche two \| Employees excluding non-executive directors
Share-Based Compensation Awards
Vesting period	36 months

Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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The risk-free interest rate assumption that is used in valuing an option on its own shares.

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

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Percentage of vesting of award under share-based payment arrangement.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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