5. Investments (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Change in fair value of investment	$ 4,108	$ 6,908
Loss on sale of investment	(3,316)	(5,590)
Net realized and unrealized gain (loss) on investment	1,318	792
Investments - Warrants [Member]
Change in fair value of investment	630	(697)
Investments - Common Stock [Member]
Change in fair value of investment	3,478	7,605
Loss on sale of investment	$ (3,316)	$ (5,590)