CUSTOMER LIABILITIES - Schedule of customer liabilities (Details) - USD ($) $ in Thousands  | 
Mar. 31, 2022  | 
Mar. 31, 2021  | 
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| Revenue, Major Customer [Line Items] | ||
| Customer liabilities | $ 766,627 | $ 671,825 | 
| Brokerage customers | ||
| Revenue, Major Customer [Line Items] | ||
| Customer liabilities | 519,516 | 547,349 | 
| Banking customers | ||
| Revenue, Major Customer [Line Items] | ||
| Customer liabilities | $ 247,111 | $ 124,476 | 
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- Definition Customer Liabilities No definition available. 
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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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