STOCK OPTIONS (Details) - USD ($) $ in Thousands		1 Months Ended			3 Months Ended		9 Months Ended
	Jan. 01, 2016	Jul. 31, 2016	Jan. 31, 2016	Mar. 31, 2015	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015	Apr. 30, 2015
Stock options
Options available to purchase/Common Stock outstanding					3,253,949		3,253,949		3,253,310
Stock-based compensation					$ 1,187	$ 1,372	$ 3,571	$ 3,614
Employee Stock Option
Stock options
Expected term							10 years
Stock option modification							$ 112
Vesting period							48 months
2007 Plan
Stock options
Options available to purchase/Common Stock outstanding					150,207		150,207		240,863
2007 Plan | Employee Stock Option
Stock options
Expected term							10 years
2010 Plan
Stock options
Number of shares expected to be granted										0
Shares available for future grants					322,355		322,355
Options available to purchase/Common Stock outstanding					1,852,726		1,852,726		2,065,687
2010 Plan | Employee Stock Option
Stock options
Expected term							10 years
2015 Plan
Stock options
Shares authorized for issuance					4,322,355		4,322,355			4,000,000
Options available to purchase/Common Stock outstanding					1,251,016		1,251,016		946,760
2015 Plan | Employee Stock Option
Stock options
Expected term							10 years
Employee Stock Purchase Plan
Stock options
Shares authorized for issuance				187,500
Percentage of outstanding shares reserved for future issuance				1.00%
Increase in shares of common stock reserved for issuance				50,000
Maximum aggregate number of shares reserved for issuance during term of employee stock purchase plan				1,250,000
Increased share reserve	50,000
Stock issued under ESPP		9,781	6,948
Offering Period							6 months
Stock-based compensation					$ 12		$ 39
Common Stock | Employee Stock Purchase Plan
Stock options
Stock issued under ESPP							16,729
Accrued expense | Employee Stock Purchase Plan
Stock options
Employee payroll deductions							$ 24