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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 | 3 Months Ended | 6 Months Ended
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Feb. 28, 2023 | Feb. 28, 2022 | Feb. 28, 2023 | Feb. 28, 2022
Earnings Per Share Disclosure [Line Items] |  |  |  |  |
Weighted average basic common shares outstanding | [1] | 32,588 | 32,582 | 32,654 | 32,546
Dilutive effect of restricted stock units | [2] | 991 | 1,066 | 1,000 | 1,063
Weighted average diluted common shares outstanding |  | 34,400 | 34,463 | 33,654 | 33,609
2.875% Convertible senior notes, due 2024 |  |  |  |  |
Earnings Per Share Disclosure [Line Items] |  |  |  |  |
Dilutive effect of convertible notes | [3] | 821 | 815 |  |
[1] | Restricted stock grants and restricted stock units that are considered participating securities, including some grants subject to certain performance criteria, are included in weighted average basic common shares outstanding when the Company is in a net earnings position.
[2] | Restricted stock units that are not considered participating securities and 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.
[3] | The dilutive effect of the 2.875% Convertible notes due 2024 was excluded for the six months ended February 28, 2023 and 2022 as they were considered anti-dilutive under the “if converted” method as further discussed below.

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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 -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 45 -Paragraph 40 -Subparagraph (c) -URI https://asc.fasb.org/extlink&oid=126958026&loc=d3e1930-109256 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 45 -Paragraph 42 -URI https://asc.fasb.org/extlink&oid=126958026&loc=d3e2029-109256 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (a) -URI https://asc.fasb.org/extlink&oid=124432515&loc=d3e3550-109257 + Details
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- Definition Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 45 -Paragraph 1 -URI https://asc.fasb.org/extlink&oid=126962052&loc=d3e4991-113900 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 45 -Paragraph 22 -URI https://asc.fasb.org/extlink&oid=126958026&loc=d3e1707-109256 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (a) -URI https://asc.fasb.org/extlink&oid=124432515&loc=d3e3550-109257 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 45 -Paragraph 28A -URI https://asc.fasb.org/extlink&oid=126958026&loc=d3e1500-109256 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 45 -Paragraph 23 -Subparagraph (c) -URI https://asc.fasb.org/extlink&oid=126958026&loc=d3e1757-109256 + Details
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- Definition The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (a) -URI https://asc.fasb.org/extlink&oid=124432515&loc=d3e3550-109257 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 45 -Paragraph 16 -URI https://asc.fasb.org/extlink&oid=126958026&loc=d3e1505-109256 + Details
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