WARRANTS - Issued with the 2018 Notes (Details) - Warrants Issued with the 2018 Notes - USD ($) $ / shares in Units, $ in Millions	Nov. 05, 2018	Feb. 05, 2018	Jan. 18, 2018
Warrants
Initial fair value recorded as debt discount (in dollars)		$ 0.1	$ 0.1
Warrants to purchase common stock (in shares)	76,847
Warrants to purchase common stock (in dollars)	$ 0.3
Exercise price (in dollars per share)	$ 6.59

Amount of increase in additional paid in capital (APIC) resulting from the issuance of warrants. Includes allocation of proceeds of debt securities issued with detachable stock purchase warrants.

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Exercise price per share or per unit of warrants or rights outstanding.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

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Amount, after accumulated amortization, of debt discount.

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