Benefit Plans - Expected Future Retiree Benefit Payments (Details) (USD $) In Thousands, unless otherwise specified	Aug. 31, 2012
Qualified Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
2013	$ 36,805
2014	39,083
2015	42,954
2016	44,523
2017	47,263
2018-2022	278,194
Non-Qualified Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
2013	3,325
2014	1,276
2015	1,002
2016	1,869
2017	4,293
2018-2022	13,187
Other Benefits, Gross
Defined Benefit Plan Disclosure [Line Items]
2013	3,297
2014	3,455
2015	3,671
2016	4,018
2017	4,249
2018-2022	23,644
Other Benefits, Medicare D
Defined Benefit Plan Disclosure [Line Items]
2013	100
2014	100
2015	100
2016	100
2017	100
2018-2022	$ 500

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Amount of benefits expected to be paid in the five fiscal years after the fifth fiscal year following the latest fiscal year from a 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 (f)

-URI http://asc.fasb.org/extlink&oid=21915506&loc=d3e1928-114920

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- Definition

Amount of benefits expected to be paid in the next fiscal year following the latest fiscal year from a defined benefit plan.

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- Definition

Amount of benefits expected to be paid in the fifth fiscal year following the latest fiscal year from a defined benefit plan.

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Amount of benefits expected to be paid in the fourth fiscal year following the latest fiscal year from a defined benefit plan.

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Amount of benefits expected to be paid in the third fiscal year following the latest fiscal year from a defined benefit plan.

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Amount of benefits expected to be paid in the second fiscal year following the latest fiscal year from a defined benefit plan.

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