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v3.21.1

STOCK-BASED COMPENSATION - Option activity (Details) - USD ($) $ / shares in Units, $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2021 | Mar. 31, 2020 | Dec. 31, 2020 | Dec. 31, 2019
Share-Based Compensation Arrangement By Share-Based Payment Award, Options, Number Of Shares Available For Grant [Roll Forward] |  |  |  |
Options available for grant, beginning of period | 11,048 | 4,299,140 | 4,299,140 |
Options granted (in shares) | (18,335) | 0 | (10,932,615) |
Options forfeited (in shares) | 18,335 |  | 870,317 |
Options available for grant, end of period | 11,048 |  | 11,048 | 4,299,140
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward] |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number, Beginning Balance | 51,379,939 | 42,846,649 | 42,846,649 |
Options granted (in shares) | 18,335 | 0 | 10,932,615 |
Options exercised (in shares) | (6,465,857) |  | (996,991) |
Options forfeited (in shares) | (18,335) |  | (870,317) |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number, Ending Balance | 44,914,082 |  | 51,379,939 | 42,846,649
Options vested and exercisable (in shares) | 32,204,617 |  | 37,219,281 |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract] |  |  |  |
Options outstanding, beginning of period, weighted average exercise price (in dollars per share) | $ 0.56 | $ 0.34 | $ 0.34 |
Options granted, weighted average exercise price (in dollars per share) | 3.47 |  | 1.23 |
Options exercised, weighted average exercise price (in dollars per share) | 0.43 |  | 0.38 |
Options forfeited, weighted average exercise price (in dollars per share) | 0.51 |  | 0.49 |
Options outstanding, end of period, weighted average exercise price (in dollars per share) | 0.58 |  | 0.56 | $ 0.34
Options vested and exercisable, weighted-average exercise price (in dollars per share) | $ 0.46 |  | $ 0.45 |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Additional Disclosures [Abstract] |  |  |  |
Weighted average remaining contractual life, options outstanding | 7 years 18 days |  | 7 years 2 months 15 days | 6 years 9 months 25 days
Weighted average remaining contractual life, options vested and exercisable | 6 years 3 months 18 days |  | 6 years 5 months 23 days |
Aggregate intrinsic value, options outstanding | $ 202,792 |  | $ 46,516 | $ 5,821
Aggregate intrinsic value, options vested and exercisable | $ 149,536 |  | $ 37,854 |

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- Definition Share-Based Compensation Arrangement By Share-Based Compensation Award, Options, Number Of Shares Available For Grant + 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 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. + 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 (c)(1)(iv)(3) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition Gross number of share options (or share units) granted during the period. + References No definition available. + 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 + Details
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- Definition Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan. + 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 (c)(1)(i) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition Amount by which current fair value of underlying stock exceeds exercise price of fully vested and expected to vest exercisable or convertible options. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur. + 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 (e)(2) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition Number of fully vested and expected to vest exercisable options that may be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur. + 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 (e)(2) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition Weighted-average exercise price, at which grantee can acquire shares reserved for issuance, for fully vested and expected to vest exercisable or convertible options. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur. + 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 (e)(2) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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- Definition Weighted average remaining contractual term for option awards outstanding, 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 (e)(1) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
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