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FAIR VALUE MEASUREMENTS - EQUITY INVESTMENT (Details) - Equity Investment - USD ($)	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	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	$ 169,000
Increase (decrease) in fair value of equity investment	(195,000)	$ 98,000
Gain (loss) related to foreign currency translation	$ (25,000)	$ 5,000
Maximum
Equity Investments [Line Item]
Cost method investments Ownership			20.00%

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