Fair value measurements - Narrative (Details) - USD ($) $ in Millions	Nov. 30, 2024	Aug. 31, 2024
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Fair value of long-term notes outstanding	$ 8,056	$ 9,549
Carrying Value
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Fair value of long-term notes outstanding	6,000	7,200
Estimate of Fair Value Measurement
Fair Value Disclosure, Asset and Liability, Not Measured at Fair Value [Line Items]
Carrying value of long-term notes outstanding	$ 5,200	$ 6,400

Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

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+ Details

- Definition

Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

+ References + Details