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DISCONTINUED OPERATIONS - Narrative (Details) - Discontinued Operations - USD ($) $ in Thousands | 12 Months Ended
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Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2023
Telephonics Corporation |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |
Disposal group, including discontinued operation, post closing adjustment | $ 8,726 | $ 7,768 |
Installation Services and Other Discontinued Activities |  |  |
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items] |  |  |
Revenue from disposed business | $ 0 | $ 0 | $ 0

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