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ORGANIZATION AND SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - CONCENTRATIONS OF CUSTOMERS AND SUPPLIERS (Details) - customer	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Concentration risk
Number of customers	2	2
Customer | Revenue
Concentration risk
Concentration risk percentage	59.00%	39.00%	81.00%

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- Definition

Represents the number of customers that accounted for the majority of the entity's revenues during the period.

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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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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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