Grant date fair value of options under share-based payment arrangement.

No definition available.

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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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- Definition

Agreed-upon price for the exchange of the underlying asset relating to the share-based payment award.

+ References

No definition available.

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- Definition

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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- Definition

The 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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- Definition

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

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- Definition

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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- Definition

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

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- Definition

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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Share Based Compensation - Performance Stock Options (Details) - USD ($) $ / shares in Units, $ in Millions		12 Months Ended
	May 06, 2024	Dec. 31, 2024	Dec. 31, 2023
Share-based compensation
Volatility (as a percent)		96.00%	97.00%
Expected life (in years)		5 years 7 months 28 days	6 years 3 days
Strike price (in dollars per share)		$ 1.62	$ 3.58
Risk-free interest rate (as a percent)		4.17%	3.97%
2019 Plan
Share-based compensation
Options granted		1,652,000	1,875,400
Weighted average fair values of options granted		$ 1.26	$ 2.87
Performance Stock Options \| 2019 Plan
Share-based compensation
Options granted	924,000
Expiration term (in years)	10 years
Original grant-date fair value	$ 1.3
Volatility (as a percent)	98.50%
Expected life (in years)	5 years 9 months 25 days
Strike price (in dollars per share)	$ 1.74
Risk-free interest rate (as a percent)	4.43%
Weighted average fair values of options granted		$ 1.38
Performance Stock Options \| 2019 Plan \| Share-based Compensation Award, Tranche One
Share-based compensation
Percentage of shares to vest		50.00%
Vesting period		6 months
Performance Stock Options \| 2019 Plan \| Share-based Compensation Award, Tranche Two
Share-based compensation
Percentage of shares to vest		50.00%
Vesting period		1 year