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Summary of Significant Accounting Policies - Interest and Foreign Exchange (Detail) - USD ($) $ in Millions | 12 Months Ended
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Aug. 31, 2024 | Aug. 31, 2023 | Aug. 31, 2022
Accounting Policies [Abstract] |  |  |
Interest and other expense | $ 93.9 | $ 79.2 | $ 55.7
Foreign exchange loss, net | 6.9 | 6.2 | 1.7
Interest and foreign exchange | $ 100.8 | $ 85.4 | $ 57.4

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