BALANCE SHEET INFORMATION - Schedule of Intangible Assets, Net (Details) - USD ($) $ in Thousands  | 
Sep. 30, 2021  | 
Mar. 31, 2021  | 
|---|---|---|
| Finite-Lived Intangible Assets | ||
| Gross | $ 11,000 | $ 5,600 | 
| Accumulated Amortization | (1,868) | (563) | 
| Net | 9,132 | 5,037 | 
| Developed technology | ||
| Finite-Lived Intangible Assets | ||
| Gross | 6,400 | 4,700 | 
| Accumulated Amortization | (1,425) | (473) | 
| Net | 4,975 | 4,227 | 
| Customer lists | ||
| Finite-Lived Intangible Assets | ||
| Gross | 4,600 | 900 | 
| Accumulated Amortization | (443) | (90) | 
| Net | $ 4,157 | $ 810 | 
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- Definition Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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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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- Definition Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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