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GOODWILL AND INTANGIBLES - Summary of gross carrying value and accumulated amortization of intangible assets (Details) - USD ($) $ in Thousands | Sep. 30, 2025 | Sep. 30, 2024
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Intangible Asset, Acquired, Finite-Lived [Line Items] |  |
Gross Carrying Amount | $ 467,799 | $ 468,134
Trademarks | 183,969 | 291,803
Total intangible assets | 651,768 | 759,937
Accumulated Amortization | 163,654 | 141,155
Customer Relationships |  |
Intangible Asset, Acquired, Finite-Lived [Line Items] |  |
Gross Carrying Amount | 449,203 | 450,784
Accumulated Amortization | $ 153,507 | 134,296
Average Life (Years) | 17 years |
Unpatented technology |  |
Intangible Asset, Acquired, Finite-Lived [Line Items] |  |
Gross Carrying Amount | $ 18,596 | 17,350
Accumulated Amortization | $ 10,147 | $ 6,859
Average Life (Years) | 10 years |

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