Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
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Accumulated change, net of tax, in accumulated gains and losses from derivative instruments designated and qualifying as the effective portion of cash flow hedges. Includes an entity's share of an equity investee's Increase or Decrease in deferred hedging gains or losses.

+ References

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The portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments representing (a) the amount of the hedge ineffectiveness and (b) the amount, if any, excluded from the assessment of hedge effectiveness.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Amount, after tax, of reclassification from accumulated other comprehensive income (AOCI) of gain (loss) from increase (decrease) in fair value of net investment hedge.

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Financial Derivatives (Narrative) (Details) € in Millions, R in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Feb. 28, 2019 USD ($)	Feb. 28, 2018 USD ($)	Feb. 28, 2019 USD ($)	Feb. 28, 2018 USD ($)	Feb. 28, 2019 ZAR (R)	Feb. 28, 2019 EUR (€)	Aug. 31, 2018 USD ($)	Aug. 31, 2018 ZAR (R)	Aug. 31, 2018 EUR (€)	Feb. 28, 2018 ZAR (R)	Feb. 28, 2018 EUR (€)
Foreign Exchange Forward [Member] \| Derivatives Not Designated As Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Outstanding foreign currency forward contracts	$ 2.0	$ 6.2	$ 2.0	$ 6.2			$ 5.0
Fair Value Hedging [Member]
Derivatives, Fair Value [Line Items]
Realized and unrealized gains, net of related income tax effects	5.7	3.0	5.7	3.0			$ 5.0
Net Investment Hedging [Member]
Derivatives, Fair Value [Line Items]
Foreign currency translation forward contracts, after tax net gain (loss)	0.2	(0.6)	0.9	(1.3)
Derivative contracts ineffective amount	$ 0.0	$ 0.0	$ 0.0	$ 0.0
Outstanding foreign currency forward contracts					R 43.0	€ 32.7		R 43.0	€ 32.7	R 43.0	€ 32.8