Annual report pursuant to Section 13 and 15(d)

SHARE-BASED COMPENSATION - Schedule of Valuation Assumptions of Stock Options (Details)

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SHARE-BASED COMPENSATION - Schedule of Valuation Assumptions of Stock Options (Details) - Stock Options
12 Months Ended
Dec. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]  
Expected volatility 113.60%
Expected dividend yields 0.00%
Risk-free rate 0.40%