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

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Stock-Based Compensation Plans - Schedule of Valuation Assumptions Used (Details)	6 Months Ended			12 Months Ended
	Jun. 30, 2026	Jun. 29, 2026	Jun. 30, 2025	Dec. 31, 2025
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected dividend yield	0.00%
SARs liability
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected dividend yield		0.00%		0.00%
Risk-free interest rate, minimum (as a percent)		4.02%		3.64%
Risk-free interest rate, maximum (as a percent)		4.34%		4.11%
Stock price volatility, minimum (as a percent)		85.00%		65.00%
Stock price volatility, maximum (as a percent)		110.00%		115.00%
Probability, occuring (as a percent)	50.00%	50.00%		50.00%
Probability, not occurring (as a percent)	50.00%	50.00%		50.00%
Minimum \| SARs liability
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term of options (years)		1 month 2 days		1 year
Maximum \| SARs liability
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term of options (years)		2 years 8 months 15 days		2 years 4 months 24 days
2019 Omnibus Equity Incentive Plan And 2026 Inducement Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate	4.20%		4.14%
Expected dividend yield	0.00%		0.00%
Expected volatility	109.40%		116.00%
Expected term of options (years)	5 years 9 months 18 days		5 years 10 months 28 days
2019 Omnibus Equity Incentive Plan \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term of options (years)	10 years