DERIVATIVE ASSETS AND DERIVATIVE LIABILITIES, Narrative (Details) - USD ($) $ in Millions |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Mar. 31, 2026 |
Mar. 31, 2025 |
Mar. 31, 2026 |
Mar. 31, 2025 |
|
| Derivative Instruments and Hedging Activities Disclosure [Abstract] | ||||
| Gain (loss) excluded from assessment of hedge effectiveness | $ 0 | $ 0 | $ 0 | $ 0 |
| Amount of interest expense expected to reclassify from AOCI | $ 6 | $ 6 | ||
| Maximum length of time hedged in cash flow hedge | 2 years | |||