Total costs accrued as of the balance sheet date for environmental loss contingencies.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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The charge against earnings in the period for known or estimated future costs arising from requirements to perform environmental remediation activities.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-SubTopic 30
-Section 50
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Amount of rent expense incurred for leased assets, including but not limited to, furniture and equipment, that is not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

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Commitments And Contingencies (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Feb. 28, 2017	Nov. 30, 2015	Aug. 31, 2017	Aug. 31, 2016	Aug. 31, 2015	Aug. 31, 2012
Site Contingency [Line Items]
Lease expense			$ 5.1	$ 5.0	$ 4.5
Lindsay, Nebraska Facility [Member]
Site Contingency [Line Items]
Environmental Remediation Expense	$ 13.0	$ 1.5				$ 7.2
Current environmental remediation accrual			$ 18.0