CONVERTIBLE PREFERRED STOCK (Tables)

12 Months Ended

Dec. 31, 2019

Temporary Equity Disclosure [Abstract]

Schedule of Preferred Stock

As of each balance sheet date, the preferred stock consisted of the following:

	December 31, 2019
	Shares authorized	Shares issued and outstanding	Carrying value		Liquidation preference		Common stock issuable upon conversion
Series A preferred stock	22,533,945	22,501,503	$	22,357	$	22,502	7,461,168
Series B preferred stock	22,917,726	22,917,726	93,479		87,225		7,599,178
Series C preferred stock	19,420,124	19,420,124	84,737		85,000		6,439,424
	64,871,795	64,839,353	$	200,573	$	194,727	21,499,770

	December 31, 2018
	Shares authorized	Shares issued and outstanding	Carrying value		Liquidation preference		Common stock issuable upon conversion
Series A convertible preferred stock	22,533,945	22,501,503	$	22,357	$	22,502	7,461,168
Series B convertible preferred stock	22,333,144	11,166,572	38,413		42,500		3,702,677
	44,867,089	33,668,075	$	60,770	$	65,002	11,163,845