DISTRIBUTIONS TO COMMON STOCKHOLDERS - Schedule of Adjustments for Permanent Book-tax Differences to Reflect Tax Character (Details) - USD ($) $ in Thousands |
12 Months Ended | |
|---|---|---|
Sep. 30, 2025 |
Sep. 30, 2024 |
|
| Equity [Abstract] | ||
| Undistributed net investment income | $ (946) | $ (1,299) |
| Accumulated net realized losses | 1,053 | 1,310 |
| Capital in excess of par value | $ (107) | $ (11) |