Postretirement and Other Employee Benefits (Accumulated Benefit Obligation in Excess of Plan Assets) (Details) - USD ($) $ in Thousands	Aug. 31, 2018	Aug. 31, 2017
Retirement Benefits [Abstract]
Projected benefit obligation	$ 161,104	$ 167,714
Accumulated benefit obligation	152,380	158,971
Fair value of plan assets	$ 151,715	$ 146,698

No definition available.

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- Definition

Amount of accumulated benefit obligation for defined benefit plan with accumulated benefit obligation in excess of plan assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e2417-114920

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-Publisher FASB
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- Definition

Amount of plan asset for defined benefit plan with accumulated benefit obligation in excess of plan assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e2417-114920

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-Publisher FASB
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-Section 50
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-URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e2417-114920

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- Definition

Amount of projected benefit obligation for defined benefit pension plan with accumulated benefit obligation in excess of plan assets.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (a)
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-Publisher FASB
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