REVENUE RECOGNITION - Schedule of Effect of New Accounting Pronouncements (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Revenue from Contract with Customer [Abstract]
Revenues	$ 134	$ 157
Prepaid expenses and other current assets	409		$ 364
Deferred revenue	204		271
Accumulated deficit	(99,701)		$ (92,564)
Net loss	$ (7,137)	$ (5,716)

Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as current.

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Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer.

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The cumulative amount of the reporting entity's undistributed earnings or deficit.

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Amount, including tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value-added and excise.

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