COMMON STOCK, TRANSACTIONS (Details) - USD ($) $ / shares in Units, $ in Thousands			1 Months Ended			3 Months Ended	6 Months Ended		12 Months Ended
	May 30, 2018	Aug. 10, 2017	Jun. 30, 2018	May 31, 2018	Jan. 31, 2018	Jun. 30, 2018	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017	Apr. 16, 2018	Aug. 11, 2017
Common stock disclosures
Common stock, par value (in dollars per share)			$ 0.00001			$ 0.00001	$ 0.00001		$ 0.00001	$ 0.00001
Proceeds from issuance of common stock and warrants, net of issuance costs							$ 16,511
Proceeds from issuance of stock under ESPP							3	$ 29
Proceeds from exercise of stock options								$ 26
Proceeds from exercise of warrants							10
401(k)
Common stock disclosures
Company contributions to employee 401(k) accounts							$ 28
2018 Series A Warrant Exercise price $2.00
Common stock disclosures
Exercise price (in dollars per unit)			2.00			2.00	$ 2.00
2018 Series B Warrant Exercise price $.01
Common stock disclosures
Exercise price (in dollars per unit)			0.01			0.01	0.01
2014 Warrant Exercise price $11.75
Common stock disclosures
Exercise price (in dollars per unit)			$ 11.75			$ 11.75	$ 11.75
2014 Warrant Exercise price $11.75 | Warrant Exchange Agreement
Common stock disclosures
Exercise price (in dollars per unit)		$ 96.75									$ 20.75
Common Stock
Common stock disclosures
Stock issued under ESPP (in shares)							188		710
Proceeds from issuance of stock under ESPP							$ 3		$ 51
Issuance of common stock upon exercise of stock options (in shares)									3,576
Proceeds from exercise of stock options									$ 26
Issuance of common stock upon exercise of warrants (in shares)									139
Proceeds from exercise of warrants									$ 3
Common Stock | Warrant Exchange Agreement
Common stock disclosures
Issuance of stock in exchange for warrants (in shares)		80,857							80,857
Common Stock | 401(k)
Common stock disclosures
Aggregate number of shares reserved for issuance				4,100
Number of additional shares reserved				4,000
Issuance of common stock to 401(k) plan (in shares)							440		3,933
Issuance of common stock to 401(k) plan							$ 6		$ 183
Common Stock | 2014 Warrant Exercise price $11.75
Common stock disclosures
Number of shares into which a warrant may be converted			307			307	307		537
Common Stock | 2014 Warrant Exercise price $11.75 | Warrant Exchange Agreement
Common stock disclosures
Number of shares into which a warrant may be converted		23,102							23,102		1,941
Underwritten Public Offering, June 2018
Common stock disclosures
Proceeds from issuance of common stock and warrants, net of issuance costs			$ 13,500
Underwritten Public Offering, June 2018 | 2018 Series A Warrant Exercise price $2.00
Common stock disclosures
Number of shares/warrants comprised in a unit (in shares)			1
Exercise price (in dollars per unit)			$ 2.00			$ 2.00	$ 2.00
Warrant expiration term (in years)			5 years
Underwritten Public Offering, June 2018 | 2018 Series B Warrant Exercise price $.01
Common stock disclosures
Exercise price (in dollars per unit)			$ 0.01			0.01	$ 0.01
Warrant expiration term (in years)			20 years
Proceeds from exercise of warrants							$ 10
Underwritten Public Offering, June 2018 | Common Stock
Common stock disclosures
Number of shares/warrants comprised in a unit (in shares)			1
Common stock, par value (in dollars per share)			$ 0.00001			$ 0.00001	$ 0.00001
Number of shares of common stock to be purchased by each warrant			1			1	1
Underwritten Public Offering, June 2018 | Common Stock | 2018 Series B Warrant Exercise price $.01
Common stock disclosures
Issuance of stock in public offering (in shares)							1,050,918
Underwritten Public Offering, June 2018 | Common Stock And Warrants
Common stock disclosures
Issuance of stock in public offering (in shares)			1,378,400
Equity issuance (in price per unit)			$ 2.00			$ 2.00	$ 2.00
Pre Funded Units
Common stock disclosures
Issuance of stock in public offering (in shares)			6,242,811
Equity issuance (in price per unit)			$ 1.99			$ 1.99	$ 1.99
Pre Funded Units | 2018 Series A Warrant Exercise price $2.00
Common stock disclosures
Number of shares/warrants comprised in a unit (in shares)			1
Pre Funded Units | 2018 Series B Warrant Exercise price $.01
Common stock disclosures
Number of shares/warrants comprised in a unit (in shares)			1
Pre Funded Units | Common Stock
Common stock disclosures
Number of shares of common stock to be purchased by each warrant			1			1	1
Purchase and registration rights agreement | Common Stock
Common stock disclosures
Issuance of stock in public offering (in shares)	17,192					83,330	256,804
Common stock, par value (in dollars per share)					$ 0.00001
Aggregate proceeds					$ 15,000
Term					24 months
Deferred offering costs	$ 627
Proceeds from issuance of common stock, net of issuance costs						$ 370	$ 3,100
Purchase and registration rights agreement | Common Stock | Maximum
Common stock disclosures
Aggregate number of shares reserved for issuance	1,200,000