SHAREHOLDERS' EQUITY (Details) - USD ($) $ / shares in Units, $ in Thousands					3 Months Ended		6 Months Ended
	Jun. 25, 2020	May 23, 2019	Mar. 29, 2019	Nov. 08, 2018	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2020	Jun. 30, 2019
Number of units issued		1,935,484	14,193,548
Price per unit			$ 1.55
Net proceeds		$ 2,600	$ 20,300
Issuance costs		$ 400	$ 1,700
Number of shares of common stock			1
Number of warrants received for each share of common stock share sold			0.5
Sale of common stock for cash, net of issuance costs								$ 22,910
Shares of common stock issued upon exercise of stock options							60,000	257,500
Proceeds from exercise of stock options							$ 61	$ 260
Weighted average exercise price of stock options (in dollars per share)							$ 1.06	$ 1.01
Maximum
Proceeds from exercise of stock options								$ 300
June 2020 Amended and Restated Credit Agreement
Number of units issued	2,091,700
Net proceeds	$ 1,900
Common Stock and Additional Paid-in Capital
Shares of common stock issued upon exercise of stock options					36,000		60,000	258,000
Warrants
Number of shares of common stock			1
Price per common share for each warrant			$ 2.00
Warrant expiration term			3 years
Subscription Receipts | Officers, directors and certain employees
Number of units issued			1,935,484
Price per unit			$ 1.55
ATM offering
Number of units issued						1,010,545
Net proceeds								$ 1,851
Aggregate offering price				$ 90,000
Sale of common stock for cash, net of issuance costs						$ 1,900
ATM offering | Common Stock and Additional Paid-in Capital
Number of units issued								1,010,000
Net proceeds								$ 1,851