Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

TREASURY STOCK (Details) - USD ($)	12 Months Ended
TREASURY STOCK (Details) - USD ($)	Dec. 31, 2020	Mar. 25, 2020	Apr. 30, 2019
TREASURY STOCK
Stock repurchase program authorized amount		$ 20,000,000
Consideration of shares repurchased	$ 2,172,819
Class A ordinary shares
TREASURY STOCK
Number of shares repurchased during the period	10,429,305
Price per share	$ 0.21		$ 8.00
Consideration of shares repurchased	$ 2,200,000
American Depositary Shares
TREASURY STOCK
Price per share	$ 3.13