Gross Carrying Amount and Accumulated Amortization of Other Intangible Assets (Details) - USD ($) $ in Thousands	3 Months Ended
Nov. 30, 2017	Aug. 31, 2017
Indefinite And Finite Lived Intangible Assets [Line Items]
Accumulated Amortization	$ 198,686	$ 192,660
Gross Carrying Value	414,718	413,149
Net Book Value	216,032	220,489
Tradenames
Indefinite And Finite Lived Intangible Assets [Line Items]
Accumulated Amortization	0	0
Net Book Value	91,825	91,080
Gross Carrying Value	$ 91,825	91,080
Customer relationships
Indefinite And Finite Lived Intangible Assets [Line Items]
Weighted Average Amortization Period (Years)	15 years
Gross Carrying Value	$ 264,409	263,498
Accumulated Amortization	158,245	153,003
Net Book Value	$ 106,164	110,495
Patents
Indefinite And Finite Lived Intangible Assets [Line Items]
Weighted Average Amortization Period (Years)	10 years
Gross Carrying Value	$ 30,448	30,401
Accumulated Amortization	24,476	24,027
Net Book Value	$ 5,972	6,374
Trademarks and tradenames
Indefinite And Finite Lived Intangible Assets [Line Items]
Weighted Average Amortization Period (Years)	18 years
Gross Carrying Value	$ 21,324	21,498
Accumulated Amortization	9,637	9,396
Net Book Value	$ 11,687	12,102
Other intangibles
Indefinite And Finite Lived Intangible Assets [Line Items]
Weighted Average Amortization Period (Years)	3 years
Gross Carrying Value	$ 6,712	6,672
Accumulated Amortization	6,328	6,234
Net Book Value	$ 384	$ 438

Indefinite And Finite Lived Intangible Assets [Line Items]

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- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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- Definition

Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

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- Definition

Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

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- Definition

Amount of assets, excluding financial assets and goodwill, lacking physical substance and having a projected indefinite period of benefit.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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- Definition

Amount before accumulated amortization of intangible assets, excluding goodwill.

+ References

No definition available.

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- Definition

Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16212-109274

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph ((a)(1),(b))
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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