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SHAREHOLDERS' EQUITY - Narrative (Details) - USD ($) $ / shares in Units, $ in Thousands |  | 12 Months Ended
--- | --- | ---
Feb. 08, 2021 | Sep. 30, 2025 | Sep. 30, 2024
Class of Stock [Line Items] |  |  |
Dividend rate | 4.875% |  |
Proceeds from issuance of preferred stock, net | $ 293,325 |  |
Stock repurchased (in shares) |  | 3,338,351 | 1,058,178
Additional shares authorized to be repurchased (in shares) |  | 8,162,654 |
Weighted average |  |  |
Class of Stock [Line Items] |  |  |
Weighted average cost of repurchased stock (in dollars per share) |  | $ 29.56 | $ 25.29
Public Offering |  |  |
Class of Stock [Line Items] |  |  |
Number of shares issued in transaction (in shares) | 12,000,000 |  |
Public offering price (in dollars per share) | $ 25.00 |  |
Public Offering | Series A Preferred Stock |  |  |
Class of Stock [Line Items] |  |  |
Number of shares issued in transaction (in shares) | 300,000 |  |

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