INTANGIBLE ASSETS, NET - Schedule of intangible assets (Details) - USD ($) $ in Thousands  | 
Mar. 31, 2022  | 
Mar. 31, 2021  | 
|---|---|---|
| Goodwill [Line Items] | ||
| Less: Accumulated amortization | $ (2,022) | $ (1,428) | 
| Intangible assets, net | 3,512 | 3,902 | 
| Client base | ||
| Goodwill [Line Items] | ||
| Intangible assets, gross | 1,843 | 2,023 | 
| Software | ||
| Goodwill [Line Items] | ||
| Intangible assets, gross | 1,389 | 1,930 | 
| Trading platform | ||
| Goodwill [Line Items] | ||
| Intangible assets, gross | 9 | 0 | 
| Licenses | ||
| Goodwill [Line Items] | ||
| Intangible assets, gross | 2,252 | 1,377 | 
| Other Intangible Assets | ||
| Goodwill [Line Items] | ||
| Intangible assets, gross | $ 41 | $ 0 | 
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- Definition Accumulated amount of 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 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 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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- 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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