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Income Taxes - Reconciliation Between Effective and Statutory Tax Rates on Continuing Operations (Detail) | 12 Months Ended
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Aug. 31, 2025 | Aug. 31, 2024 | Aug. 31, 2023 | Aug. 31, 2019 | Aug. 31, 2018 | Aug. 31, 2017
Income Tax Disclosure [Abstract] |  |  |  |  |  |
Federal statutory rate | 21.00% | 21.00% | 21.00% | 21.00% | 25.70% | 35.00%
State income taxes, net of federal benefit | 2.00% | 1.40% | 3.00% |  |  |
Foreign operations | 2.00% | 4.60% | 6.20% |  |  |
U.S. tax on foreign earnings | 0.70% | 2.30% | 4.50% |  |  |
U.S. impact of foreign branch | 2.30% | (1.90%) |  |  |  |
Permanent differences | 1.20% | 4.00% | (5.80%) |  |  |
BEAT and minimum taxes | 4.40% | 0.50% | 1.60% |  |  |
Change in valuation allowance | (0.80%) | 2.80% | (0.50%) |  |  |
Uncertain tax positions | 0.30% | 0.70% | 1.40% |  |  |
Noncontrolling interest in flow-through entity | (0.30%) | (0.30%) | (2.70%) |  |  |
Credits | (0.80%) | (4.70%) | 0.10% |  |  |
Other | 0.10% | (2.70%) | (1.80%) |  |  |
Effective tax rate | 32.10% | 27.70% | 27.00% |  |  |

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- Definition Percentage of domestic federal statutory tax rate applicable to pretax income (loss). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 235 -SubTopic 10 -Name Accounting Standards Codification -Section S50 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org/1943274/2147480738/235-10-S50-1 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 12 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482685/740-10-50-12 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 55 -Paragraph 231 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482663/740-10-55-231 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 6.I.1.Q1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147479360/740-10-S99-1 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Topic 235 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08(h)(2)) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480678/235-10-S99-1 + Details
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