CUSTOMER LIABILITIES - Schedule of customer liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Mar. 31, 2021
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