Description of share purchase agreement.

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Exercised warrants to purchase ordinary shares.

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Investment in affiliate company textual.

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Investment in affiliate cost.

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Number of installments.

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Percentage of diluted basis.

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Purchased shares of ordinary shares.

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Number of warrants or rights outstanding.

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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 gain (loss) included in earnings for investments classified as other.

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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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Sum of the carrying amounts as of the balance sheet date of all investments.

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Per share or per unit amount of equity securities issued.

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Investment in Affiliate Company (Details Textual) $ / shares in Units, $ in Thousands						1 Months Ended	12 Months Ended
	Jan. 10, 2018 shares	Oct. 06, 2017 USD ($) $ / shares	Sep. 05, 2017 USD ($) $ / shares	Nov. 07, 2016 USD ($) $ / shares shares	Aug. 04, 2016 USD ($) Installments	Aug. 25, 2016 USD ($) $ / shares shares	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2015 USD ($)
Investment in Affiliate Company (Textual)
Investment amounts							$ 1,404	$ 1,248
Other investments amount								66
Investment in affiliate amount								1,356
Private placements gross amount								1,733
Equity in net loss (gain) of an affiliated company							156	(108)
Operations of financial income							$ 3,967
Rail Vision Ltd. [Member]
Investment in Affiliate 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
Investment amounts					$ 1,600			$ 1,422
Equity method investment, percentage							24.76%	32.00%
Price per share \| $ / shares		$ 270.19	$ 270.19
Percentage of diluted basis							35.97%	48.00%
Private placements gross amount		$ 5,800	$ 5,800
Equity in net loss (gain) of an affiliated company							$ 1,258
Operations of financial income							$ 3,967
Rail Vision Ltd. [Member] \| Subsequent Events [Member]
Investment in Affiliate Company (Textual)
Exercised warrants to purchase ordinary shares \| shares	11,486
Rail Vision Ltd. [Member] \| Company [Member] \| First installment [Member]
Investment in Affiliate Company (Textual)
Investment amounts					$ 600	$ 600
Equity method investment, percentage					13.50%
Purchased ordinary shares \| shares						7,093
Price per share \| $ / shares						$ 84.59
Warrants shares \| shares						16,157
Other investments amount						$ 29
Investment in affiliate amount						$ 571
Rail Vision Ltd. [Member] \| Company [Member] \| Second installment [Member]
Investment in Affiliate Company (Textual)
Investment amounts				$ 822	$ 1,000
Equity method investment, percentage					36.00%
Purchased ordinary shares \| shares				16,599
Price per share \| $ / shares				$ 46.52
Warrants shares \| shares				33,931
Other investments amount				$ 37
Investment in affiliate amount				$ 785
Other investors [Member]
Investment in Affiliate Company (Textual)
Investment amounts					$ 2,000