The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Amount of income (loss) for proportionate share of equity method investee's income (loss).

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Related Party Transactions - Equity-Method Investment (Details Textual) - USD ($)	3 Months Ended		6 Months Ended	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Jun. 30, 2019	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018	Jun. 30, 2018
Related Party Transaction [Line Items]
Share of gain (losses) for investee	$ 303,000	$ (47,000)		$ 15,000	$ (47,000)
Equity investments	$ 303,000			$ 303,000		$ 288,000
ADAIR Technology [Member]
Related Party Transaction [Line Items]
Equity method ownership percentage							30.00%
Share of gain (losses) for investee			$ (600,000)
Equity investments			$ 0
ADAIR Technology [Member] \| Minimum [Member]
Related Party Transaction [Line Items]
Equity method ownership percentage							20.00%