Income Taxes (Reconciliations of Unrecognized Tax Benefits) (Details) - USD ($) $ in Millions	12 Months Ended
	Aug. 31, 2021	Aug. 31, 2020	Aug. 31, 2019
Reconciliation of Unrecognized Tax Benefits [Roll Forward]
Beginning balance	$ 190	$ 164	$ 257
Additions for tax positions of prior years	15	10	20
Reductions for tax positions of prior years	(3)	(9)	(106)
Additions for tax positions related to current year	36	27	36
Cash settlements	0	(1)	0
Reductions from lapses in statutes of limitations	(2)	(1)	(3)
Reductions from non-cash settlements with taxing authorities	0	(2)	(36)
Foreign exchange rate adjustment	5	2	(4)
Ending balance	241	190	164
Unrecognized tax benefits that would affect the effective tax rate (if recognized)	$ 139	$ 109	$ 93