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Derivative Instruments - Effect of Derivative Instruments on Accumulated Other Comprehensive Loss and Statements of Income (Detail) - Cash Flow Hedging - USD ($) $ in Millions | 12 Months Ended
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Aug. 31, 2025 | Aug. 31, 2024 | Aug. 31, 2023
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Gain (loss) recognized in OCI on derivatives | $ 8.5 | $ 3.2 | $ 32.4
Gain (loss) reclassified from AOCL | 16.8 | 18.7 | 12.8
Foreign Exchange Contracts |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Gain (loss) recognized in income on derivatives | $ (0.3) | $ 0.1 | $ 0.0
Derivative, Gain (Loss), Statement of Income or Comprehensive Income [Extensible Enumeration] | Interest And Foreign Exchange Net | Interest And Foreign Exchange Net | Interest And Foreign Exchange Net
Foreign Exchange Contracts | Sales |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Gain (loss) recognized in OCI on derivatives | $ 1.5 | $ 3.4 | $ 5.6
Gain (loss) reclassified from AOCL | 3.9 | 2.5 | (0.2)
Foreign Exchange Contracts | Cost of Revenue |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Gain (loss) recognized in OCI on derivatives | 0.1 | (0.6) | 2.0
Gain (loss) reclassified from AOCL | 0.1 | (0.5) | 2.2
Interest Rate Swap Contracts | Interest and Foreign Exchange |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Gain (loss) recognized in OCI on derivatives | 6.9 | 0.4 | 24.8
Gain (loss) reclassified from AOCL | $ 12.8 | $ 16.7 | $ 10.8

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- Definition Amount of increase (decrease) in the fair value of derivatives recognized in the income statement. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 815 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 4A -Subparagraph (b)(1) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480434/815-10-50-4A Reference 2: http://www.xbrl.org/2003/role/exampleRef -Name Accounting Standards Codification -Section 55 -Paragraph 10 -SubTopic 10 -Topic 825 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482881/825-10-55-10 + Details
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