SHARE-BASED COMPENSATION- Assumptions Used to Value the Company's Options Grants (Details)	12 Months Ended
Dec. 31, 2021 $ / shares	Dec. 31, 2020
Exercise price (USD)	$ 0.0925
Risk-free interest rate Minimum	0.24%
Risk-free interest rate Maximum	0.33%
Expected term (in years)	6 years
Expected dividend yield	0.00%
Expected volatility Minimum	52.96%
Expected volatility Maximum	55.13%
Expected forfeiture rate (post-vesting)	5.00%
Fair value of the underlying shares on the date of options grants (US$)	$ 0.23
Fair value of share option (US$)	$ 0.15
Maximum [Member]
Exercise multiple	2.8
Minimum [Member]
Exercise multiple	2.2

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

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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 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.

+ References

No definition available.

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- Definition

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.

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

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

+ References

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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.

+ References

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- Definition

Price of a single share of a number of saleable stocks of a company.

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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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- Definition

SharebasedCompensationArrangementBySharebasedPaymentAwardFairValueAssumptionsExerciseMultiple

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- Definition

Share-based compensation arrangement by share-based payment award, fair value assumptions, expected forfeiture rate.

+ References

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