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INCOME TAXES - Narrative (Details) - USD ($) $ in Thousands | 12 Months Ended
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Sep. 30, 2025 | Sep. 30, 2024
Income Tax Examination [Line Items] |  |
Valuation allowance increase (decrease) | $ 3,714 | $ 8,997
Undistributed earnings of foreign subsidiaries | 122,964 |
Undistributed earnings of foreign subsidiaries, amount previously subjected to federal income tax | 38,703 |
Unremitted foreign earnings | 1,514 | 1,896
Deferred tax assets, valuation allowance | 30,703 | 26,989
Potential tax benefits impact on effective tax rate | 1,603 |
Liability for uncertainty in income taxes, current | 402 | 310
Domestic Tax Authority |  |
Income Tax Examination [Line Items] |  |
Operating loss carryforwards | 0 | 0
Tax credit carryforward amount | 5,933 | 5,933
Non-U.S. Tax Authority |  |
Income Tax Examination [Line Items] |  |
Operating loss carryforwards | 75,849 | 63,217
State and Local Jurisdiction |  |
Income Tax Examination [Line Items] |  |
Operating loss carryforwards | $ 221,855 | $ 228,485

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