STOCK-BASED COMPENSATION - Weighted Average Assumptions used to Estimate Fair Value of all Options at Grant Date using Black-Scholes-Merton Option-Pricing Model (Detail) |
12 Months Ended | ||
|---|---|---|---|
Sep. 30, 2026 |
Sep. 30, 2025 |
Sep. 30, 2024 |
|
| Share-Based Payment Arrangement [Abstract] | |||
| Risk-free interest rate, minimum | 3.90% | 4.00% | 4.10% |
| Risk-free interest rate, maximum | 4.50% | 4.50% | 4.70% |
| Expected life of options | 6 years 6 months | 6 years 6 months | 6 years 6 months |
| Expected dividend yield of stock | 0.00% | 0.00% | 0.00% |
| Expected volatility of stock | 32.50% | 32.50% | 33.50% |