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
-Sentence Column B

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- Definition

The effective portion of gain or loss included in accumulated other comprehensive income on derivative instruments designated and qualifying as hedging instruments.

+ References

No definition available.

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5624171-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 25
-Section 50
-Paragraph 1
-Subparagraph (a)(1),(2)
-URI http://asc.fasb.org/extlink&oid=6886632&loc=d3e76258-113986

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- Definition

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.

+ References

No definition available.

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Financial Derivatives (Narrative) (Details) € in Millions, ZAR in Millions, $ in Millions	3 Months Ended		6 Months Ended		12 Months Ended
	Feb. 28, 2017 USD ($)	Feb. 29, 2016 USD ($)	Feb. 28, 2017 USD ($)	Feb. 29, 2016 USD ($)	Aug. 31, 2016 USD ($)	Feb. 28, 2017 ZAR	Feb. 28, 2017 EUR (€)	Aug. 31, 2016 ZAR	Aug. 31, 2016 EUR (€)	Feb. 29, 2016 ZAR	Feb. 29, 2016 EUR (€)
Foreign Exchange Forward [Member]
Derivatives, Fair Value [Line Items]
Foreign currency translation forward contracts, after tax net gains (losses)	$ 1.0	$ 1.4	$ 0.9	$ 1.2
Foreign Exchange Forward [Member] \| Derivatives Not Designated As Hedging Instruments [Member]
Derivatives, Fair Value [Line Items]
Outstanding foreign currency forward contracts	5.6	10.3	5.6	10.3	$ 8.2
Fair Value Hedging [Member]
Derivatives, Fair Value [Line Items]
Realized and unrealized gains, net of related income tax effects			6.3	6.2	$ 5.6
Net Investment Hedging [Member]
Derivatives, Fair Value [Line Items]
Foreign currency translation forward contracts, after tax net gains (losses)	$ 0.0	$ 0.0	$ 0.0	$ 0.0
Outstanding foreign currency forward contracts						ZAR 43.0	€ 32.9	ZAR 43.0	€ 32.6	ZAR 43.0	€ 28.3