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Income Taxes - Additional information (Detail) - USD ($) | 12 Months Ended
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Aug. 31, 2022 | Aug. 31, 2021 | Aug. 31, 2020 | Aug. 31, 2019 | Aug. 31, 2018 | Aug. 31, 2017
Operating Loss Carryforwards [Line Items] |  |  |  |  |  |
Income tax and earnings from unconsolidated affiliates,Domestic u.s. operations | $ 12,400,000 | $ (30,700,000) | $ 71,200,000 |  |  |
Income tax and earnings from unconsolidated affiliates,Foreign operations | $ 48,200,000 | $ 22,100,000 | $ 53,600,000 |  |  |
Statutory federal corporate tax rate | 21.00% | 21.00% | 21.00% | 21.00% | 25.70% | 35.00%
Federal income tax expense (benefit), CARES Act | $ 38,500,000 |  |  |  |  |
Inflation reduction act terms | On August 16, 2022, the Inflation Reduction Act (the “IRA”) was signed into law. In general, the provisions of the IRA will be effective beginning with fiscal year 2023, with certain exceptions. The IRA includes a new 15% corporate minimum tax as well as a 1% excise tax on corporate stock repurchases applicable to repurchases after December 31, 2022. The Company is in the process of evaluating the potential impacts of the IRA and does not currently expect the IRA to have a material impact on our effective tax rate. However, the analysis is ongoing and incomplete, and it is possible that the IRA could have an adverse effect on the Company’s tax liability. |  |  |  |  |
Deferred tax assets, valuation allowance | $ 9,900,000 | $ 10,400,000 |  |  |  |
Net increase (decrease) in the valuation allowance | 500,000 |  |  |  |  |
Unrecognized tax benefits, excluding interest | 400,000 | 1,600,000 |  |  |  |
Accrued interest related to uncertain tax provisions | 100,000 | 400,000 |  |  |  |
Increase (reduction) in interest expense relating to reserves for uncertain tax provisions | 300,000 | $ 600,000 |  |  |  |
Accrued penalties related to uncertain tax reserves | 0 |  |  |  |  |
State |  |  |  |  |  |
Operating Loss Carryforwards [Line Items] |  |  |  |  |  |
Operating loss carryforwards | $ 104,800,000 |  |  |  |  |
Operating loss carryforwards expiration year | 2026 |  |  |  |  |
Credit carryforwards | $ 1,200,000 |  |  |  |  |
Credit carryforwards expiration year | 2022 |  |  |  |  |
Foreign |  |  |  |  |  |
Operating Loss Carryforwards [Line Items] |  |  |  |  |  |
Operating loss carryforwards | $ 33,500,000 |  |  |  |  |
Operating loss carryforwards expiration year | 2022 |  |  |  |  |
Operating loss carryforwards that do not expire | $ 26,100,000 |  |  |  |  |

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