STOCKHOLDERS' EQUITY - Summary of Assumptions of Fair Value of Option Pricing Granted (Details) - Employee Stock Options - 2021 Equity Incentive Plan - $ / shares	3 Months Ended	12 Months Ended
Mar. 31, 2026	Mar. 31, 2025	Dec. 31, 2025	Dec. 31, 2024
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Expected volatility	109.21%
Expected volatility, minimum			91.88%	89.41%
Expected volatility, maximum			119.61%	94.48%
Expected term (years)	5 years 3 months
Risk-free interest rate	3.68%
Risk-free interest rate, minimum			4.36%	3.93%
Risk-free interest rate, maximum			4.39%	4.35%
Expected dividend yield	0.00%		0.00%	0.00%
Exercise price (in dollars per share)	$ 4.45
Minimum
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Expected term (years)			5 years 3 months 7 days	5 years 6 months
Exercise price (in dollars per share)		$ 6.08	$ 2.38	$ 14.88
Maximum
Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items]
Expected term (years)		6 years 7 days	6 years 7 days	6 years 7 days
Exercise price (in dollars per share)		$ 7.6	$ 7.6	$ 19.2

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

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

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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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