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EMPLOYEES' RETIREMENT PLANS (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Aug. 31, 2019	Aug. 31, 2018	Aug. 31, 2017
BRP plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Deferred compensation liability	$ 45.7	$ 49.3
Current value of segregated assets	56.3	56.2
Net holding gain on segregated assets	3.3	9.3	$ 7.5
Other Long-term Liabilities | BRP plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Deferred compensation liability	39.9	42.8
Accrued Expenses and Other Payables | BRP plan
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Deferred compensation liability	5.8	6.5
Minimum
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Expected future employer contributions in fiscal 2020	1.0
United States
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Compensation expense under defined contribution profit sharing and savings plan and BRP Plan	$ 32.9	$ 27.3	$ 28.3

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Aggregate carrying value as of the balance sheet date of the liabilities for all deferred compensation arrangements payable beyond one year (or the operating cycle, if longer).

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