CUSTOMER LIABILITIES - Schedule of customer liabilities (Details) - USD ($) $ in Thousands  | 
12 Months Ended | |
|---|---|---|
Mar. 31, 2024  | 
Mar. 31, 2023  | 
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| Interest-bearing deposits: | ||
| Term deposits | $ 1,221,072 | $ 832,751 | 
| Non-interest-bearing deposits: | ||
| Total non-interest-bearing accounts | 1,052,758 | 1,092,496 | 
| Total customer liabilities | 2,273,830 | 1,925,247 | 
| Term deposits | ||
| Interest-bearing deposits: | ||
| Term deposits | $ 1,221,072 | $ 832,751 | 
| Minimum | Term deposits | ||
| Interest-bearing deposits: | ||
| Interest rate | 0.04% | 0.10% | 
| Maximum | Term deposits | ||
| Interest-bearing deposits: | ||
| Interest rate | 17.30% | 16.90% | 
| Brokerage customers | ||
| Non-interest-bearing deposits: | ||
| Total non-interest-bearing accounts | $ 742,902 | $ 633,542 | 
| Current customer accounts | ||
| Non-interest-bearing deposits: | ||
| Total non-interest-bearing accounts | $ 309,856 | $ 458,954 | 
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- Definition The average effective interest rate during the reporting period. Reference 1: http://www.xbrl.org/2003/role/disclosureRef 
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- Definition The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition The aggregate of all domestic and foreign interest-bearing deposit liabilities. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- Definition The aggregate amount of all domestic and foreign noninterest-bearing deposits liabilities held by the entity. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- References No definition available. 
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