FAIR VALUE MEASUREMENTS - EQUITY INVESTMENT (Details) - Equity Investment - USD ($)	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2007
Equity Investments [Line Item]
Number of shares owned					13,842,625
Cost method investments cost basis					$ 0
Fair value of equity investment	$ 582,000		$ 582,000
Increase (decrease) in fair value of equity investment	(98,000)	$ (350,000)	0	$ (475,000)
Gain (loss) related to foreign currency translation	$ (8,000)	$ (38,000)	$ (3,000)	$ (38,000)

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Amount before tax of foreign currency transaction unrealized gain (loss) recognized in the income statement.

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Amount of increase (decrease) of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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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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Balance held at close of period in number of shares.

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