Share Capital - Additional Information (Details)	6 Months Ended
Jun. 30, 2019 shares
Share Capital [Line Items]
Options exercised	3,837,716
Ordinary shares issued upon option exercise	3,837,716
ESPP
Share Capital [Line Items]
Ordinary shares available for grants	3,078,989
Shares issued under plan	390,614
2015 Plan
Share Capital [Line Items]
Ordinary shares available for grants	11,986,679
2015 Plan \| Option
Share Capital [Line Items]
Stock awards granted, vesting period	4 years
Stock awards granted, expiration period	10 years
2015 Plan \| RSUs
Share Capital [Line Items]
Stock awards granted, vesting period	3 years

Ordinary shares issued upon option exercise.

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- Definition

Share capital.

+ References

No definition available.

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

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.

+ References

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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- Definition

Number of shares issued during the period as a result of an employee stock purchase plan.

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

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