NET GAIN ON TRADING SECURITIES - Schedule of net gain on trading securities (Details) - USD ($) $ in Thousands |
3 Months Ended | |
|---|---|---|
Jun. 30, 2026 |
Jun. 30, 2025 |
|
| Investments, Debt and Equity Securities [Abstract] | ||
| Net gain recognized during the period on trading securities sold during the period | $ 25,279 | $ 7,866 |
| Net unrealized gain recognized during the reporting period on trading securities still held at the reporting date | 54,499 | 37,736 |
| Net gain recognized during the period on trading securities | $ 79,778 | $ 45,602 |