Fair Value Measurements (Assets Held for Sale) (Details) - USD ($) $ in Millions	Aug. 31, 2021	Aug. 31, 2020
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Assets held for sale, assets with fair value exceeding carrying value	$ 30
Level 2
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Assets held for sale, assets with carrying value approximating fair value	31
Carrying Amount
Fair Value Measurement Inputs and Valuation Techniques [Line Items]
Assets held-for-sale	$ 61	$ 67