Share Capital - Schedule of Stock Options to Purchase Ordinary Shares (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Number of options
Number of options, Outstanding at beginning of year	14,806,027
Number of options, Granted	2,520,502
Number of options, Exercised	(2,693,236)
Number of options, Forfeited and cancelled	(195,078)
Number of options, Outstanding at ending of year	14,438,215	14,806,027
Number of options, Exercisable options	6,090,628
Weighted average exercise price
Weighted average exercise price, Outstanding at beginning of year	$ 10.64
Weighted average exercise price, Granted	23.73	$ 10.53	$ 7.37
Weighted average exercise price, Exercised	6.89
Weighted average exercise price, Forfeited and cancelled	15.09
Weighted average exercise price, Outstanding at end of year	13.56	$ 10.64
Weighted average exercise price, Exercisable options	$ 11.04
Aggregate intrinsic value
Aggregate intrinsic value, Outstanding at end of year	$ 287,706
Aggregate intrinsic value, Exercisable options	$ 136,695

Share based compensation arrangement by share based payment award options intrinsic value.

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Gross number of share options (or share units) granted during the period.

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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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Number of options outstanding, including both vested and non-vested options.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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Number of share options (or share units) exercised during the current period.

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