Benefit Plans - Expected Future Retiree Benefit Payments (Details) (USD $) In Thousands, unless otherwise specified	Aug. 31, 2014
Qualified Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
2015	$ 35,797
2016	44,287
2017	49,495
2018	49,844
2019	52,956
2020-2024	295,700
Non-Qualified Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
2015	3,222
2016	721
2017	3,474
2018	1,461
2019	5,575
2020-2024	23,145
Other Benefits, Gross
Defined Benefit Plan Disclosure [Line Items]
2015	2,787
2016	2,911
2017	3,085
2018	3,222
2019	3,280
2020-2024	18,101
Other Benefits, Medicare D
Defined Benefit Plan Disclosure [Line Items]
2015	100
2016	100
2017	100
2018	100
2019	100
2020-2024	$ 500

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Amount of benefits from a defined benefit plan expected to be paid in the five fiscal years after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ 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=35743120&loc=d3e1928-114920

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- Definition

Amount of benefits from a defined benefit plan expected to be paid in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of benefits from a defined benefit plan expected to be paid in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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- Definition

Amount of benefits from a defined benefit plan expected to be paid in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of benefits from a defined benefit plan expected to be paid in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of benefits from a defined benefit plan expected to be paid in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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