Retirement benefits (Details) - USD ($) $ in Millions	3 Months Ended
	Nov. 30, 2021	Nov. 30, 2020
Components of net periodic benefit costs [Abstract]
Total net periodic pension costs (income)	$ (33)	$ (45)
Employer cash contributions to defined benefit pension plans	1
Expected employer cash contributions to defined benefit plan in current fiscal year	40
Selling, general and administrative expenses
Components of net periodic benefit costs [Abstract]
Service costs	1	1
Other expense
Components of net periodic benefit costs [Abstract]
Interest costs	39	33
Other income
Components of net periodic benefit costs [Abstract]
Expected returns on plan assets/other	(74)	(80)
United States
Components of net periodic benefit costs [Abstract]
Profit sharing provision expense	69	57
Foreign Plan
Components of net periodic benefit costs [Abstract]
Cost recognized in the consolidated condensed statements of earnings	$ 25	$ 26