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Summary of Significant Accounting Policies - Interest and Foreign Exchange (Detail) - USD ($) $ in Thousands | 12 Months Ended
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Aug. 31, 2021 | Aug. 31, 2020 | Aug. 31, 2019
Accounting Policies [Abstract] |  |  |
Interest and other expense | $ 44,655 | $ 42,386 | $ 32,260
Foreign exchange (gain) loss | (1,392) | 1,233 | (1,348)
Interest and foreign exchange | $ 43,263 | $ 43,619 | $ 30,912

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