Share Capital - Schedule of Stock Option Plan (Details)	3 Months Ended
Mar. 31, 2019 $ / shares shares
Number of options
Number of options, Outstanding at beginning of year \| shares	14,438,215
Number of options, Granted \| shares	751,471
Number of options, Exercised \| shares	(2,047,421)
Number of options, Forfeited and cancelled \| shares	(40,258)
Number of options, Outstanding at ending of year \| shares	13,102,007
Number of options, Exercisable options \| shares	5,852,344
Weighted average exercise price
Weighted average exercise price, Outstanding at beginning of year \| $ / shares	$ 13.56
Weighted average exercise price, Granted \| $ / shares	47.04
Weighted average exercise price, Exercised \| $ / shares	8.38
Weighted average exercise price, Forfeited and cancelled \| $ / shares	14.47
Weighted average exercise price, Outstanding at end of year \| $ / shares	16.29
Weighted average exercise price, Exercisable options \| $ / shares	$ 12.79

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

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

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