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Earnings Per Share - Reconciliation of Shares Used in Computation of Basic and Diluted Earnings Per Common Share (Detail) - shares shares in Thousands | 12 Months Ended
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Aug. 31, 2025 | Aug. 31, 2024 | Aug. 31, 2023
Earnings Per Share Disclosure [Line Items] |  |  |  |
Weighted average basic common shares outstanding |  | 31,171 | 31,102 | 31,983
Dilutive effect of restricted stock units | [1] | 968 | 916 | 992
Weighted average diluted common shares outstanding |  | 32,139 | 32,363 | 33,799
2.875% Convertible senior notes, due 2024 |  |  |  |
Earnings Per Share Disclosure [Line Items] |  |  |  |
Dilutive effect of convertible notes | [2] |  | 345 | 824
[1] | Restricted stock units subject to performance criteria, for which actual levels of performance above target have been achieved, are included in weighted average diluted common shares outstanding when the Company is in a net earnings position.
[2] | The 2.875% Convertible notes due 2024 were retired on February 1, 2024.

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- Definition Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of convertible debt securities using the if-converted method. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 260 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 1 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482662/260-10-50-1 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 260 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 42 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482689/260-10-45-42 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 260 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 40 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482689/260-10-45-40 + Details
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