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Income Taxes - Additional information (Detail) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Aug. 31, 2024 | Aug. 31, 2023 | Aug. 31, 2022 | 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 | $ 111.4 | $ 32.2 | $ 12.4 |  |  |
Income tax and earnings from unconsolidated affiliates,Foreign operations | $ 112.3 | $ 58.8 | $ 48.2 |  |  |
Statutory federal corporate tax rate | 21.00% | 21.00% | 21.00% | 21.00% | 25.70% | 35.00%
Carryback of 2021 loss | $ 22.8 |  |  |  |  |
Deferred tax assets, valuation allowance | 15.9 | $ 9.6 |  |  |  |
Net increase (decrease) in the valuation allowance | 6.3 |  |  |  |  |
Accrued interest related to uncertain tax provisions | 0.8 | 0.6 |  |  |  |
Increase (reduction) in interest expense relating to reserves for uncertain tax provisions | 0.2 | $ 0.5 | $ (0.3) |  |  |
Federal |  |  |  |  |  |
Operating Loss Carryforwards [Line Items] |  |  |  |  |  |
Credit carryforwards | 15.4 |  |  |  |  |
Operating loss carryforwards that do not expire | 67.4 |  |  |  |  |
State |  |  |  |  |  |
Operating Loss Carryforwards [Line Items] |  |  |  |  |  |
Operating loss carryforwards | $ 193.0 |  |  |  |  |
Operating loss carryforwards expiration year | 2029 |  |  |  |  |
Credit carryforwards | $ 0.9 |  |  |  |  |
Credit carryforwards expiration year | 2025 |  |  |  |  |
Foreign |  |  |  |  |  |
Operating Loss Carryforwards [Line Items] |  |  |  |  |  |
Operating loss carryforwards | $ 9.9 |  |  |  |  |
Operating loss carryforwards expiration year | 2024 |  |  |  |  |
Operating loss carryforwards that do not expire | $ 26.2 |  |  |  |  |

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- Definition Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482685/740-10-50-2 + Details
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