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INCOME TAXES - Schedule of Effective Income Tax Rate Reconciliation (Details) | 12 Months Ended
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Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2023
Income Tax Disclosure [Abstract] |  |  |
U.S. Federal statutory income tax rate | 21.00% | 21.00% | 21.00%
State and local taxes, net of Federal benefit | 5.50% | 3.70% | (0.20%)
Non-U.S. taxes - foreign permanent items and taxes | 3.00% | 1.00% | 1.40%
Change in tax contingency reserves | 0.00% | (0.50%) | (0.40%)
Tax Reform-Repatriation of Foreign Earnings and GILTI | (2.10%) | (0.50%) | 0.50%
Change in valuation allowance | 2.70% | 2.80% | 3.90%
Other non-deductible/non-taxable items, net | (0.005) | 0 | 0
Non-deductible officer's compensation | 5.60% | 1.90% | 5.10%
Research and U.S. foreign tax credits | (0.90%) | (0.30%) | (0.90%)
Goodwill impairment | 27.40% | 0.00% | 0.00%
Share based compensation | (2.80%) | (0.70%) | 0.80%
Other | 1.00% | 0.80% | (0.10%)
Effective tax rate | 59.90% | 29.20% | 31.10%

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- Definition Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 12 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482685/740-10-50-12 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 231 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482663/740-10-55-231 + Details
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- Definition Percentage of domestic federal statutory tax rate applicable to pretax income (loss). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 235 -SubTopic 10 -Name Accounting Standards Codification -Section S50 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480738/235-10-S50-1 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 12 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482685/740-10-50-12 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 231 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482663/740-10-55-231 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 6.I.1.Q1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479360/740-10-S99-1 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 235 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08(h)(2)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480678/235-10-S99-1 + Details
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