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INCOME TAXES - Narratives (Detail) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Sep. 30, 2026 | Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2023
Income Tax Contingency [Line Items] |  |  |  |
Statutory tax rate |  | 21.00% | 21.00% | 21.00%
Net operating losses |  | $ 59.0 | $ 52.0 |
US and non-US Tax Credit Carryforward |  | $ 9.0 |  |
US and non-US tax credit carryforward expiration period |  | 2026 |  |
Effect of unrecognized tax benefits on effective tax rate |  | $ 23.0 | 14.0 |
Accrual for income tax penalties and interest |  | 5.0 | 4.0 |
Deferred Federal Income Tax Expense (Benefit) |  | (32.0) | $ (6.0) | $ 28.0
Undistributed Earnings of Foreign Subsidiaries |  | 30.0 |  |
Forecast |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Unrecognized Tax Benefits, Expected Reduction | $ 2.0 |  |  |
State |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Net operating losses |  | $ 780.0 |  |
Minimum |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Operating Loss Carryforwards, Expiration Year |  | 2026 |  |
Maximum |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Operating Loss Carryforwards, Expiration Year |  | 2045 |  |
UNITED KINGDOM | Foreign Country Jurisdiction |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Net operating losses |  | $ 93.0 |  |
GERMANY | Foreign Country Jurisdiction |  |  |  |
Income Tax Contingency [Line Items] |  |  |  |
Net operating losses |  | $ 66.0 |  |

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- Definition Amount of deferred federal tax expense (benefit) attributable to income (loss) from continuing operations. Includes, but is not limited to, deferred national tax expense (benefit) for non-US (United States of America) jurisdiction. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -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/2009/role/commonPracticeRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 6.I.7) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479360/740-10-S99-1 Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 235 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08(h)(1)(Note 1)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480678/235-10-S99-1 Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 9 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482685/740-10-50-9 + Details
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