CONVERTIBLE NOTES (Schedule of Interest Expense Recognized) (Details) - 2018 Notes [Member] $ in Thousands	12 Months Ended
Dec. 31, 2018 USD ($)
Contractual interest expense	$ 139
Amortization of debt issuance costs and debt discount	15
Gain from early redemption	(32)
Total	$ 122

Amount of gain from early redemption of debt.

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Amount of amortization expense attributable to debt discount (premium) and debt issuance costs.

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Amount of the cost of borrowed funds accounted for as interest expense.

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Represents the portion of interest incurred in the period on debt arrangements that was charged against earnings, excluding amortization of debt discount (premium) and financing costs.

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