5. INVESTMENTS (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Investment Holdings [Line Items]
Change in fair value of investment	$ 2,677	$ 6,980	$ 6,785	$ 13,888
Loss on sale of investment			(2,762)	(7,232)
Net realized and unrealized gain (loss) on investment	3,231	5,338	4,023	6,656
Warrant Investment [Member]
Investment Holdings [Line Items]
Change in fair value of investment	2,677	3,091	3,306	2,394
Gain on sale of investment	554	0	554	0
Common Stock Investment [Member]
Investment Holdings [Line Items]
Change in fair value of investment	0	3,889	3,479	11,494
Loss on sale of investment	$ 0	$ (1,642)	$ (3,316)	$ (7,232)

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

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