EQUITY INCENTIVE PLAN, Assumptions Used to Value Option Grants (Details)	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Employees [Member]
Employees and Nonemployees [Abstract]
Expected dividend yield	0.00%		0.00%
Expected volatility			70.00%
Employees [Member] \| Minimum [Member]
Employees and Nonemployees [Abstract]
Risk-free interest rate	0.90%		1.40%
Expected term	5 years 6 months		5 years
Expected volatility	54.00%
Employees [Member] \| Maximum [Member]
Employees and Nonemployees [Abstract]
Risk-free interest rate	1.40%		1.90%
Expected term	6 years 3 months 18 days		6 years 2 months 12 days
Expected volatility	70.00%
Nonemployees [Member]
Employees and Nonemployees [Abstract]
Expected dividend yield		0.00%	0.00%
Expected volatility		70.00%	70.00%
Nonemployees [Member] \| Minimum [Member]
Employees and Nonemployees [Abstract]
Risk-free interest rate		0.30%	1.40%
Expected term		5 years	4 years
Nonemployees [Member] \| Maximum [Member]
Employees and Nonemployees [Abstract]
Risk-free interest rate		0.60%	1.90%
Expected term		6 years	10 years

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- Definition

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.

+ References

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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

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(i)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.D.2)
-URI http://asc.fasb.org/extlink&oid=122041274&loc=d3e301413-122809

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