Aggregate amount of ordinary shares sold.

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Basis of presentation and summary of significant accounting policies.

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Business combination recognized identifiable assets acquired and liabilities assumed cash and equivalents and short-term investments.

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Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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Date when the acquirer obtains control of the acquiree, in CCYY-MM-DD format.

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Face amount or stated value per share of common stock.

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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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The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

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No definition available.

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Cash received from principal payments made on loans related to operating activities.

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The cumulative amount of the reporting entity's undistributed earnings or deficit.

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Number of shares of stock issued during the period pursuant to acquisitions.

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Ratio applied to the conversion of stock split, for example but not limited to, one share converted to two or two shares converted to one.

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Description of the reverse stock split arrangement. Also provide the retroactive effect given by the reverse split that occurs after the balance sheet date but before the release of financial statements.

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Number of previously issued common shares repurchased by the issuing entity and held in treasury.

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Basis of Presentation and Summary of Significant Accounting Policies (Details Textual)			3 Months Ended		9 Months Ended
	Oct. 12, 2018 USD ($)	Nov. 15, 2017 ₪ / shares shares	Sep. 30, 2018 USD ($) shares	Sep. 30, 2017 shares	Sep. 30, 2018 USD ($) shares	Sep. 30, 2017 shares	Oct. 31, 2018 USD ($)	Sep. 30, 2018 ₪ / shares	Dec. 31, 2017 USD ($) shares	Dec. 31, 2017 ₪ / shares
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Business merger date		Nov. 15, 2017
Common stock, par value \| ₪ / shares								₪ 0.07		₪ 0.07
Reverse split of ordinary shares		1-for-7			1- for- 7
Reverse split of ordinary shares, ratio		0.1429			0.1429
Accumulated deficit			$ (43,863,000)		$ (43,863,000)				$ (23,089,000)
Cash equivalents and short-term investments acquired			$ 36,400,000		$ 36,400,000
Ownership percentage			30.00%		30.00%
Antidilutive securities excluded from computation of earnings per share \| shares			98,000	3,754,290	91,000	3,242,513
Treasury shares \| shares			43,000		43,000				43,000
Minimum [Member]
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Equity method ownership percentage			20.00%		20.00%
Subsequent Event [Member] \| Sales Agreement [Member] \| Leerink Partners LLC [Member] \| Maximum [Member]
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Aggregate amount of ordinary shares sold							$ 30,000,000
Term Loan [Member] \| Subsequent Event [Member] \| Western Alliance Bank [Member] \| Loan and Security Agreement [Member]
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Gross proceeds from term loan agreement	$ 10,000,000
Alocobra Limited [Member]
Basis Of Presentation And Summary Of Significant Accounting Policies [Line Items]
Stock issued during period, shares, acquisitions \| shares		6,631,712
Common stock, par value \| ₪ / shares		₪ 0.07