TRADING AND AVAILABLE-FOR-SALE SECURITIES AT FAIR VALUE - Narrative (Details) $ in Thousands  | 
12 Months Ended | |
|---|---|---|
| 
 Mar. 31, 2022  
USD ($)  
issuer 
 | 
 Mar. 31, 2021  
USD ($) 
 | 
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| Defined Benefit Plan Disclosure [Line Items] | ||
| Number of issuers | issuer | 2 | |
| Ministry of Finance of the Republic of Kazakhstan | ||
| Defined Benefit Plan Disclosure [Line Items] | ||
| Percentage of trading securities (in percent) | 10.00% | 10.00% | 
| Debt securities | $ 328,951 | $ 232,958 | 
| Kazakhstan Sustainability Fund JSC | ||
| Defined Benefit Plan Disclosure [Line Items] | ||
| Percentage of trading securities (in percent) | 10.00% | 10.00% | 
| Debt securities | $ 396,680 | $ 232,601 | 
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- Definition Number of Debt Securities Issuers No definition available. 
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- Definition Percentage Of Trading Securities No definition available. 
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- Definition Amount, after allowance for credit loss, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), investment in debt security measured at amortized cost (held-to-maturity), and investment in debt security measured at fair value with change in fair value recognized in net income (trading). 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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- Details 
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- Details 
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