Description of share purchase agreement.

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The amount of exercise of Warrant investment .

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Investment in affiliate cost.

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Percentage of diluted basis.

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Purchased shares of ordinary shares.

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

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This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.

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Investment in Affiliated Company (Details Textual) $ / shares in Units, $ in Thousands						1 Months Ended		4 Months Ended	12 Months Ended
	Nov. 01, 2018 USD ($) shares	Jul. 12, 2018 USD ($) shares	Jan. 10, 2018 USD ($) shares	Nov. 07, 2016 USD ($) $ / shares shares	Aug. 04, 2016 Installments	Oct. 31, 2017 USD ($)	Sep. 30, 2017 USD ($)	May 31, 2018 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Investment in Affiliated Company (Textual)
Investment amounts									$ 7,568	$ 1,404
Other investments amount										66
Private placements gross amount										1,733
Equity in net loss (gain) of an affiliated company									(2,905)	156	$ (108)
Operations of financial income									316	3,967
Aggregate contribution on Warrant									9,069
Aggregate contribution paid in cash									5,065		1,422
Fair value of the exercised warrants									$ (2,071)	$ 12,180	$ (1,847)
Rail Vision Ltd [Member]
Investment in Affiliated Company (Textual)
Description of share purchase agreement					The Company entered into a Share Purchase Agreement ("SPA") to acquire up to 36% of Rail Vision Ltd. ("Rail Vision") shares at an average price per share of USD 60 and 3 types of Warrants to purchase ordinary shares of Rail Vision: Warrant 1, Warrant 2 and Warrant 3 exercisable within 18 months, 30 months and 24 months at an exercise price of USD 189, USD 270 and USD 216, respectively.
Number of installments \| Installments					2
Equity method investment, percentage	35.91%					24.76%	24.76%		35.91%
Percentage of diluted basis	33.81%					35.97%	35.97%		33.81%	48.00%
Private placements gross amount						$ 5,843	$ 5,843	$ 2,700
Equity in net loss (gain) of an affiliated company						$ 1,258	$ 1,258	$ 453	$ 1,258
Exercised warrants to purchase ordinary shares \| shares	26,396	26,396	26,396
Operations of financial income									$ 3,967
Aggregate contribution on Warrant	$ 9,096	$ 9,096	$ 9,096
Aggregate contribution paid in cash	5,065	5,065	5,065
Fair value of the exercised warrants	$ 4,004	$ 4,004	$ 4,004
Rail Vision Ltd [Member] \| Minimum [Member]
Investment in Affiliated Company (Textual)
Equity method investment, percentage								29.71%
Rail Vision Ltd [Member] \| Maximum [Member]
Investment in Affiliated Company (Textual)
Equity method investment, percentage								32.74%
Rail Vision Ltd [Member] \| Warrant 1 [Member]
Investment in Affiliated Company (Textual)
Exercised warrants to purchase ordinary shares \| shares	23,692	23,692	23,692
Rail Vision Ltd [Member] \| Warrant 3 [Member]
Investment in Affiliated Company (Textual)
Exercised warrants to purchase ordinary shares \| shares	2,704	2,704	2,704
Rail Vision Ltd [Member] \| Parent Company [Member]
Investment in Affiliated Company (Textual)
Investment amounts				$ 1,422
Equity method investment, percentage				32.00%
Purchased ordinary shares \| shares				23,692
Price per share \| $ / shares				$ 60
Other investments amount				$ 66
Investment in affiliate amount				$ 1,356
Percentage of diluted basis				48.00%
Rail Vision Ltd [Member] \| Parent Company [Member] \| Warrant 1 [Member]
Investment in Affiliated Company (Textual)
Purchased ordinary shares \| shares				23,692
Rail Vision Ltd [Member] \| Parent Company [Member] \| Warrant 2 [Member]
Investment in Affiliated Company (Textual)
Purchased ordinary shares \| shares				23,692
Rail Vision Ltd [Member] \| Parent Company [Member] \| Warrant 3 [Member]
Investment in Affiliated Company (Textual)
Purchased ordinary shares \| shares				2,704