Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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STOCK AWARD PLAN AND STOCK-BASED COMPENSATION - Additional Information (Details) - USD ($)	1 Months Ended	6 Months Ended	9 Months Ended
	Dec. 31, 2017	Jun. 30, 2020	Sep. 30, 2020	Sep. 30, 2019
Stock Award Plan and Stock-Based Compensation
Fair value of common stock on grant date (in dollars per share)			$ 4.32
Total intrinsic value of the stock options exercised			$ 900,000	$ 200,000
Dividend yield (as a percent)			0.00%
Total fair value of shares vested			$ 61,000	$ 0
Employee Stock Option
Stock Award Plan and Stock-Based Compensation
Fair value of common stock on grant date (in dollars per share)			$ 1.62	$ 3.26
Total unrecognized compensation costs			$ 11,800,000
Weighted-average period over which unrecognized compensation costs is expected to be recognized			2 years 2 months 4 days
Dividend yield (as a percent)			0.00%	0.00%
Restricted Stock Units
Stock Award Plan and Stock-Based Compensation
Total unrecognized compensation costs			$ 100,000
Weighted-average period over which unrecognized compensation costs is expected to be recognized			2 months 12 days
Vesting rights percentage			25.00%
Vesting period			4 years
Description of vesting rights			RSUs awarded to employees generally vest one-fourth per year over four years from the anniversary of the date of grant
2013 Equity Incentive Plan \| Common Stock
Stock Award Plan and Stock-Based Compensation
Increase in number of shares authorized for issuance		2,000,000
2013 Equity Incentive Plan \| Employee Stock Option \| Common Stock \| Rick Russell
Stock Award Plan and Stock-Based Compensation
Shares issued	775,000
2013 Equity Incentive Plan \| Restricted Stock Units \| Common Stock \| Rick Russell
Stock Award Plan and Stock-Based Compensation
Shares issued	40,000