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Stock-based awards - Textual (Details) - shares |  | 1 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | ---
Jun. 18, 2019 | Jun. 30, 2019 | Mar. 31, 2021 | Jan. 31, 2021 | Dec. 31, 2020 | Jan. 31, 2020
Share-based awards |  |  |  |  |  |
Number of shares remained available for grant |  |  | 8,113,230 |  | 6,404,819 |
2018 Stock option and grant plan |  |  |  |  |  |
Share-based awards |  |  |  |  |  |
Number of shares of common stock issued | 3,071,960 |  |  |  |  |
Number of shares remained available for grant | 107,635 |  | 2,119,349 |  | 2,148,019 |
2019 Stock option and incentive plan |  |  |  |  |  |
Share-based awards |  |  |  |  |  |
Number of shares remained available for grant | 107,635 |  |  |  |  |
Number of shares initially reserved for issuance |  | 2,572,457 |  |  |  |
Number of additional shares reserved for issuance |  |  |  | 1,389,665 |  | 1,142,713
Percent of shares reserved and available for issuance automatically increase annually on January 1 |  | 4.00% |  |  |  |
Percentage of exercise price per share of stock options |  | 100.00% |  |  |  |
Percentage of minimum exercise price, holding more than 10% of voting power |  | 110.00% |  |  |  |
Stock options vesting period |  | 4 years |  |  |  |
2019 Employee stock purchase plan |  |  |  |  |  |
Share-based awards |  |  |  |  |  |
Number of shares initially reserved for issuance | 273,869 |  |  |  |  |
Number of additional shares reserved for issuance |  |  |  | 347,416 |  | 285,678
Percent of shares reserved and available for issuance automatically increase annually on January 1 |  | 1.00% |  |  |  |
Number of shares reserved and available for issuance automatically increase annually on January 1 (in shares) |  | 410,803 |  |  |  |
Maximum | 2019 Stock option and incentive plan |  |  |  |  |  |
Share-based awards |  |  |  |  |  |
Term of stock option |  | 10 years |  |  |  |

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- Definition Aggregate number of additional common shares reserved for future issuance. + References No definition available. + Details
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- Definition Represents the information pertaining to incentive options granted to any person possessing more than 10% of the total combined voting power of all classes of shares may not have an exercise price of less than 110% of the fair market value of the common stock on the grant date. + References No definition available. + Details
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- Definition Represents the information pertaining to exercise price per share of stock options. + References No definition available. + Details
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- Definition Percentage of annual increase of shares authorized for issuance under the plan. + References No definition available. + Details
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- Definition Annual increase of number of shares authorized for issuance under the plan. + References No definition available. + Details
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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 + Details
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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 + Details
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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 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 + Details
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- Definition Number of shares issued under share-based payment arrangement. + 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 + Details
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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. + 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)(2) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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