REVENUE - TIMING OF REVENUE RECOGNITION (Details) - USD ($) $ in Thousands |
9 Months Ended | |
|---|---|---|
Jun. 30, 2026 |
Jun. 30, 2025 |
|
| Timing of Revenue Recognition [Roll Forward] | ||
| Customers' credit, beginning | $ 31,297 | $ 38,595 |
| Increase for customers' credits | (15,090) | (14,711) |
| Customers' credit, end | 16,207 | 23,884 |
| Billed | ||
| Timing of Revenue Recognition [Roll Forward] | ||
| Billed, beginning | 109,366 | 105,531 |
| Increase for customer accounts receivable | 81,413 | 67,730 |
| Billed, end | 190,779 | 173,261 |
| Unbilled | ||
| Timing of Revenue Recognition [Roll Forward] | ||
| Billed, beginning | 24,194 | 20,094 |
| Increase for customer accounts receivable | 3,495 | 1,815 |
| Billed, end | $ 27,689 | $ 21,909 |