CONVERTIBLE PREFERRED STOCK AND STOCKHOLDERS' EQUITY - Restricted Stock Units (Details) - USD ($) $ in Thousands |
9 Months Ended | 12 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2020 |
Sep. 30, 2019 |
Dec. 31, 2019 |
Dec. 31, 2018 |
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| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||||
| Weighted-average period | 3 years 9 months 18 days | 1 year | ||
| Total expense recognized | $ 4,228 | $ 3,430 | $ 5,215 | $ 2,965 |
| RSU | ||||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||||
| Vesting period | 4 years | |||
| Unrecognized compensation costs, non-vested RSUs | $ 4,100 | |||
| Weighted-average period | 3 years 10 months 24 days | |||
| Total expense recognized | $ 200 | |||
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- Definition Amount of expense for award under share-based payment arrangement. Excludes amount capitalized. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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. No definition available.
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- Details
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