Retirement Plans (Schedule of Expected Benefit Payments) (Details) - USD ($) $ in Thousands	Aug. 31, 2018	Aug. 31, 2017	Aug. 31, 2016
Compensation And Retirement Disclosure [Abstract]
2019	$ 518
2020	511
2021	504
2022	496
2023	487
Thereafter	3,889
Net amount recognized	$ 6,404	$ 6,825	$ 7,426

No definition available.

Name:	us-gaap_CompensationAndRetirementDisclosureAbstract
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- Definition

Amount of actuarial present value of benefits attributed to service rendered by employee for defined benefit plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

+ Details

Name:	us-gaap_DefinedBenefitPlanBenefitObligation
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Balance Type:	credit
Period Type:	instant

- Definition

Amount of benefits for defined benefit plan expected to be paid in five fiscal years after fifth fiscal year following latest fiscal year.

+ References