Description of Business and Summary of Significant Accounting Policies (Change in AOCI, Net of Tax) (Details) - USD ($) $ in Millions	12 Months Ended
	Aug. 31, 2021	Aug. 31, 2020	Aug. 31, 2019
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance	$ 1,825	$ 1,900	$ 1,962
Other comprehensive income (loss) before reclassifications	65
Amounts reclassified from AOCI	(56)
Total other comprehensive income (loss)	9	49	(63)
Ending Balance	2,137	1,825	1,900
Foreign Currency Translation Adjustment
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance	(37)
Other comprehensive income (loss) before reclassifications	17
Amounts reclassified from AOCI	0
Total other comprehensive income (loss)	17
Ending Balance	(20)	(37)
Derivative Instruments
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance	(30)
Other comprehensive income (loss) before reclassifications	35
Amounts reclassified from AOCI	(41)
Total other comprehensive income (loss)	(6)
Ending Balance	(36)	(30)
Actuarial Gain (Loss)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance	34
Other comprehensive income (loss) before reclassifications	33
Amounts reclassified from AOCI	(16)
Total other comprehensive income (loss)	17
Ending Balance	51	34
Prior Service (Cost) Credit
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance	(1)
Other comprehensive income (loss) before reclassifications	(20)
Amounts reclassified from AOCI	1
Total other comprehensive income (loss)	(19)
Ending Balance	(20)	(1)
AOCI Attributable to Parent
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Beginning Balance	(34)	(83)	(20)
Total other comprehensive income (loss)	9	49	(63)
Ending Balance	$ (25)	$ (34)	$ (83)