5. INVESTMENTS (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Investment Holdings [Line Items]
Change in fair value of investment	$ (3,081)	$ (4,266)	$ 3,704	$ 9,622
Loss on sale of investment			(2,762)	(8,147)
Net realized and unrealized gain (loss) on investment	(3,081)	(5,181)	942	1,475
Warrant Investment [Member]
Investment Holdings [Line Items]
Change in fair value of investment	(3,081)	(3,216)	225	(822)
Gain on sale of investment	0	0	554	0
Common Stock Investment [Member]
Investment Holdings [Line Items]
Change in fair value of investment	0	(1,050)	3,479	10,444
Loss on sale of investment	$ 0	$ (915)	$ (3,316)	$ (8,147)

Amount of realized and unrealized gain (loss) on investment.

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