SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Warranty Reserve (Details) - USD ($) $ in Thousands |
3 Months Ended | 12 Months Ended | |
|---|---|---|---|
Mar. 31, 2021 |
Dec. 31, 2020 |
Dec. 31, 2019 |
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| SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES | |||
| Standard assurance warranty period | 1 year | 1 year | |
| Movement in Standard Product Warranty Accrual [Roll Forward] | |||
| Warranty reserve, at the beginning of the year | $ 1,553 | $ 1,491 | $ 116 |
| Additions to warranty reserve | 86 | 346 | 2,352 |
| Claims fulfilled | $ (152) | (284) | (977) |
| Warranty reserve, at the end of the period | $ 1,553 | $ 1,491 | |
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- Definition Term of standard assurance warranty. No definition available.
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- References No definition available.
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
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- Definition Amount as of the balance sheet date of the aggregate standard product warranty liability. Does not include the balance for the extended product warranty liability. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of decrease in the standard product warranty accrual from payments made in cash or in kind to satisfy claims under the terms of the standard product warranty. Excludes extended product warranties. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of increase in the standard product warranty accrual from warranties issued. Excludes extended product warranties. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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