Share-Based Compensation - Assumptions Used to Estimate Fair Values of Share Options Granted (Details)	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected volatility, minimum	70.00%
Expected volatility, maximum	71.00%
Share options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Risk-free rate of return, minimum	3.70%	3.50%	3.50%
Risk-free rate of return, maximum	4.10%	4.50%	4.70%
Expected term (in years)	6 years 3 months	6 years 3 months
Estimated volatility rate		70.00%	70.00%
Expected dividend rate	0.00%	0.00%	0.00%
Share options, batch one
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term (in years)			6 years
Share options, batch two
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term (in years)			6 years 3 months
Share options, batch three
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term (in years)			6 years 6 months

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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The estimated measure of the maximum percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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The estimated measure of the minimum percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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

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

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- Definition

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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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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