MARKETABLE SECURITIES AND FAIR VALUE MEASUREMENTS - Assets measured at fair value on a recurring basis (Details 1) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Corporate debt securities-short term	$ 9,303	$ 15,859
Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	2,947	12,923
Total	12,250	28,782
Fair Value, Measurements, Recurring | Corporate debt securities
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Corporate debt securities-short term	9,303	15,859
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets (Level 1)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents	2,947	12,923
Total	2,947	12,923
Fair Value, Measurements, Recurring | Quoted Prices in Active Markets (Level 1) | Corporate debt securities | Short term
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Corporate debt securities-short term
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents
Total	9,303	15,859
Fair Value, Measurements, Recurring | Significant Other Observable Inputs (Level 2) | Corporate debt securities | Short term
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Corporate debt securities-short term	9,303	15,859
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Cash equivalents
Total
Fair Value, Measurements, Recurring | Significant Unobservable Inputs (Level 3) | Corporate debt securities | Short term
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Corporate debt securities-short term