FAIR VALUES OF ASSETS AND LIABILITIES (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Assets and liabilities measured at fair value on a recurring basis
Marketable securities		$ 11,577
Derivative warrant liability	$ 4	1,314
Recurring basis
Assets and liabilities measured at fair value on a recurring basis
Cash equivalents	12,887	21,353
Marketable securities		11,577
Derivative warrant liability	4	1,314
Recurring basis | Level 1
Assets and liabilities measured at fair value on a recurring basis
Cash equivalents	12,887	21,353
Recurring basis | Level 2
Assets and liabilities measured at fair value on a recurring basis
Marketable securities		11,577
Derivative warrant liability	$ 4	$ 1,314