ACCOUNTS RECEIVABLE - Allowance for doubtful accounts (Details) - USD ($) $ in Thousands |
3 Months Ended | 12 Months Ended | |
|---|---|---|---|
Mar. 31, 2021 |
Dec. 31, 2020 |
Dec. 31, 2019 |
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| ACCOUNTS RECEIVABLE | |||
| Balance at beginning of period | $ 500 | $ 199 | |
| Provision for uncollectible accounts | 72 | 377 | $ 199 |
| Uncollectible accounts written off | (208) | (76) | |
| Balance at end of period | $ 364 | $ 500 | $ 199 |
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- Definition Amount of allowance for credit loss on accounts receivable, classified as current. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of direct write-downs of accounts receivable charged against the allowance. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of expense (reversal of expense) for expected credit loss on accounts receivable. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References No definition available.
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