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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, 2022 | Aug. 31, 2021 | Aug. 31, 2020
Accounting Policies [Abstract] |  |  |
Interest and other expense | $ 55.7 | $ 44.7 | $ 42.4
Foreign exchange (gain) loss | 1.7 | (1.4) | 1.2
Interest and foreign exchange | $ 57.4 | $ 43.3 | $ 43.6

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