SHARE-BASED COMPENSATION - Fair value assumptions for share options (Details) - year	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Share-Based Payment Arrangements [Abstract]
Expected volatility	56.69%	51.20%
Risk-free interest rate	1.41%	1.73%
Expected lives (in years)	1.1	5.7

Share-Based Payment Arrangements [Abstract]

No definition available.

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- Definition

The expected volatility of the share price used to calculate the fair value of the share options granted. Expected volatility is a measure of the amount by which a price is expected to fluctuate during a period. The measure of volatility used in option pricing models is the annualised standard deviation of the continuously compounded rates of return on the share over a period of time.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Name IFRS
-Number 2
-IssueDate 2020-01-01
-Paragraph 47
-Subparagraph a
-Clause i
-URI http://eifrs.ifrs.org/eifrs/xifrs-link?type=IFRS&num=2&code=ifrs-tx-2020-en-r&anchor=para_47_a_i&doctype=Standard
-URIDate 2020-01-01

+ Details

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- Definition

The option life of share options granted.

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+ Details

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- Definition

The implied yield currently available on zero-coupon government issues of the country in whose currency the exercise price for share options granted is expressed, with a remaining term equal to the expected term of the option being valued (based on the option's remaining contractual life and taking into account the effects of expected early exercise). [Refer: Government [member]]

+ References

+ Details

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