INVESTMENT AT FAIR VALUE (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Investment Holdings [Line Items]
Change in fair value of investment	$ 0	$ (3,081)	$ (2,752)	$ 3,704
Change in fair value of investment	0	3,081	2,752	(3,704)
Loss on sale of investment			515
Loss on sale of investment			(515)
Net realized and unrealized gain (loss) on investment	0	3,081	839	942
Net realized and unrealized gain (loss) on investment	0	(3,081)	(839)	(942)
Warrant Investment [Member]
Investment Holdings [Line Items]
Change in fair value of investment	0	3,081	2,752	225
Change in fair value of investment	0	(3,081)	(2,752)	(225)
Gain on sale of investment	0	0	3,591	554
Common Stock Investment [Member]
Investment Holdings [Line Items]
Change in fair value of investment	0	0	0	3,479
Change in fair value of investment	$ 0	0	0	(3,479)
Loss on sale of investment		0	0	3,316
Loss on sale of investment		$ 0	$ 0	$ (3,316)

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

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