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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Amount of cost expensed and capitalized for award under share-based payment arrangement.

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Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

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Shareholders' Equity (Details) - USD ($) $ / shares in Units, $ in Thousands		12 Months Ended
	Oct. 20, 2017	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Shareholders' Equity (Details) [Line Items]
Ordinary shares issued		5,189
Ordinary shares held by the company		30,843
Restricted Stock Units (RSUs) [Member]
Shareholders' Equity (Details) [Line Items]
Shares available for future grants		35,100	388,020
Stock option vesting period			4 years
Weighted average fair values of options granted (in Dollars per share)		$ 9.31	$ 7.86	$ 19.68
Compensation cost (in Dollars)		$ 2,107	$ 1,887	$ 1,359
Unrecognized costs related to non-vested share-based compensation (in Dollars)		$ 2,277
Recognized over a weighted average period		11 months 26 days
Restricted Stock Units (RSUs) [Member] \| Minimum [Member]
Shareholders' Equity (Details) [Line Items]
Stock option vesting period		2 years
Restricted Stock Units (RSUs) [Member] \| Maximum [Member]
Shareholders' Equity (Details) [Line Items]
Stock option vesting period		4 years
2013 Share Option Plan [Member]
Shareholders' Equity (Details) [Line Items]
Ordinary shares issued		600,001
Shares available for future grants		340,000
Increase number of shares reserved under share option plan		2,450,000
Employee Stock Option [Member]
Shareholders' Equity (Details) [Line Items]
Weighted average fair values of options granted (in Dollars per share)		$ 3.41
Follow-on public offering [Member]
Shareholders' Equity (Details) [Line Items]
Ordinary shares issued	1