RESTRICTED CASH - Schedule of restricted cash (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Mar. 31, 2021
Cash and Cash Equivalents [Line Items]
Restricted cash	$ 404,718	$ 437,958
Brokerage customers’ cash
Cash and Cash Equivalents [Line Items]
Restricted cash	394,756	427,233
Deferred distribution payments
Cash and Cash Equivalents [Line Items]
Restricted cash	8,534	8,534
Reserve with Central Bank of Russia
Cash and Cash Equivalents [Line Items]
Restricted cash	1,330	1,758
Guaranty deposits
Cash and Cash Equivalents [Line Items]
Restricted cash	$ 98	$ 433