CUSTOMER DEPOSITS - Customer Deposit Liability (Details)	9 Months Ended
	Sep. 30, 2020 USD ($)
Changes in deferred revenue and customer deposit liability
Balance as of December 31, 2019	$ 562,803
Additional deposits received	3,140,017
Less: Deposits recognized as revenue	(3,253,616)
Less: Refunds to customers	(146,263)
Balance as of September 30, 2020	$ 302,941