Represents the number of options forfeited after termination of one plan became available in 2019 plan.

No definition available.

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- Definition

Aggregate number of common shares reserved for future issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.29)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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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

+ Details

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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Period Type:	instant

- Definition

Percentage of vesting of award under share-based payment arrangement.

+ References

+ Details

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- Details

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- Details

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- Details

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- Details

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Shareholders' equity - Share-based compensation (Details) - shares	3 Months Ended	12 Months Ended
	Mar. 31, 2021	Dec. 31, 2018	Jan. 01, 2021	Dec. 31, 2020	Mar. 31, 2020	Dec. 31, 2019
2011 Plan
Share-based compensation
Options outstanding	2,063,334			2,080,087	2,305,826	2,364,526
Number of options forfeited after termination of one plan		72,186
2019 Plan
Share-based compensation
Options outstanding	3,568,890			1,706,190	982,550	220,140
Shares reserved for issuance	4,562,467		1,193,119	980,229	3,316,239
Shares available for future grants	992,327
Options \| 2011 Plan
Share-based compensation
Vesting period	4 years
Options \| 2011 Plan \| Share-based Compensation Award, Tranche One
Share-based compensation
Percentage of shares to vest	25.00%
Options \| 2011 Plan \| Share-based Compensation Award, Tranche Two
Share-based compensation
Percentage of shares to vest	2.70%
Options \| 2019 Plan
Share-based compensation
Vesting period	4 years
Options \| 2019 Plan \| Share-based Compensation Award, Tranche One
Share-based compensation
Percentage of shares to vest	25.00%
Options \| 2019 Plan \| Share-based Compensation Award, Tranche Two
Share-based compensation
Percentage of shares to vest	2.70%