Share Option Plans and ESPP - Additional Information (Details)	9 Months Ended
Sep. 30, 2021 shares
Share Capital [Line Items]
Options exercised (in shares)	918,859
ESPP
Share Capital [Line Items]
Ordinary shares available for grants (in shares)	4,989,076
Shares issued under plan (in shares)	918,859
2015 Plan
Share Capital [Line Items]
Ordinary shares available for grants (in shares)	14,467,854
2015 Plan \| Options
Share Capital [Line Items]
Stock awards granted, vesting period (years)	4 years
Stock awards granted, expiration period (years)	10 years
2015 Plan \| Restricted share units
Share Capital [Line Items]
Stock awards granted, vesting period (years)	3 years
2015 Plan \| PSUs \| Minimum
Share Capital [Line Items]
Stock awards granted, vesting period (years)	3 years
2015 Plan \| PSUs \| Maximum
Share Capital [Line Items]
Stock awards granted, vesting period (years)	6 years

Share capital.

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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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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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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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