5. Investments (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Loss on sale of investment	$ (915)	$ (3,705)	$ (8,147)	$ (3,705)
Change in fair value of investment	(4,266)	(24,211)	9,622	(53,961)
Net realized and unrealized gain (loss) on investment	(5,181)	(27,916)	1,475	(57,666)
Investments - Warrants [Member]
Change in fair value of investment	(3,216)	(5,067)	(822)	(9,848)
Investments - Common Stock [Member]
Change in fair value of investment	$ (1,050)	$ (19,144)	$ 10,444	$ (44,113)

Amount of unrealized gain (loss) on investment in debt and equity securities.

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

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The difference between the carrying value and the sale price of an investment. A loss would be recognized when the sale price of the investment is less than the carrying value of the investment. This element refers to the Loss included in earnings and not to the cash proceeds of the sale.

+ References

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The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of investments, not including unrealized gains or losses on securities separately or otherwise categorized as trading, available-for-sale, or held-to-maturity, held at each balance sheet date and included in earnings for the period.

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