Amount of actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

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Amount of increase (decrease) in benefit obligation of defined benefit plan.

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Amount of benefit for defined benefit plan expected to be paid in next fiscal year following current fiscal year.

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Percentage of plan assets to benefit obligation of defined benefit plan.

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Amount of gain (loss) recognized in net periodic benefit (cost) credit from event reducing expected years of future service of present employees or eliminating accrual of defined benefits for some or all future services of present employees.

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Amount of cost for defined contribution plan.

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Amount of discretionary contributions made by an employer to a defined contribution plan.

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Amount of cash outflow for pension benefit. Includes, but is not limited to, employer contribution to fund plan asset and payment to retiree. Excludes other postretirement benefit.

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Retirement benefits - additional information (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Aug. 31, 2018	Aug. 31, 2020	Aug. 31, 2019	Aug. 31, 2018
Defined Benefit Plan Disclosure [Line Items]
Defined benefit pension plan, investments holding percentage		75.00%	85.00%
Cash contributions to defined benefit pension plans		$ 39.0
United States
Defined Benefit Plan Disclosure [Line Items]
Profit sharing provision expense		227.0	$ 239.0	$ 217.0
Contributions to profit sharing		226.0	234.0	366.0
Foreign Plan
Defined Benefit Plan Disclosure [Line Items]
Cost recognized in the consolidated condensed statements of earnings		119.0	124.0	$ 142.0
Postretirement Health Benefit Plan
Defined Benefit Plan Disclosure [Line Items]
Reduction in benefit plan obligation	$ 201.0
Curtailment gain	$ 112.0
Defined benefit plan obligation		182.0	$ 161.0
Expected benefit to be paid net of estimated federal subsidy during fiscal year 2021		$ 10.6