Amount of expense (income) related to adjustment to fair value of warrant liability.

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The amount by which the fair value of an investment is less than the amortized cost basis or carrying amount of that investment at the balance sheet date and the decline in fair value is deemed to be other than temporary, before considering whether or not such amount is recognized in earnings or other comprehensive income.

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Amount of investment in equity method investee and investment in and advance to affiliate.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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15. Investment in Affiliates (Details Narrative) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Schedule of Equity Method Investments [Line Items]
Investment in affilates	$ 69,606	$ 69,606
EnSync [Member]
Schedule of Equity Method Investments [Line Items]
Investment in affilates	0	0
Decrease in fair value of warrant	(0)	0	$ (2,328)
Impairment of investment	0	2,214	$ 9,895
EnSync [Member] \| Convertible Preferred Stock [Member]
Schedule of Equity Method Investments [Line Items]
Investment in affilates	$ 0	0
EnSync [Member] \| Purchased Common Stock [Member]
Schedule of Equity Method Investments [Line Items]
Investment shares owned	8,000,000
EnSync [Member] \| Warrants [Member]
Schedule of Equity Method Investments [Line Items]
Investment shares owned	50,000,000
Sinsin [Member]
Schedule of Equity Method Investments [Line Items]
Investment in affilates	$ 69,606	$ 69,606