Benefit Plans - Schedule of Changes in the Fair value of the Plan's Level 3 Valued Assets (Details) (Pension Plans, Defined Benefit, USD $) In Thousands, unless otherwise specified	12 Months Ended
Aug. 31, 2014	Aug. 31, 2013
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balances at beginning of period	$ 23,621	$ 18,252
Unrealized gains (losses)	663	1,897
Realized losses (gains)	266	72
Sales	(18,630)	(24)
Purchases	5,786	3,418
Transfers out of level 3	(255)
Transfers Into Level 3		6
Total	11,451	23,621
Other Investment Companies [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balances at beginning of period	1,940	1,868
Unrealized gains (losses)	(3)	(4)
Realized losses (gains)	79	82
Sales	(12)	(12)
Purchases	0	0
Transfers out of level 3	(255)
Transfers Into Level 3		6
Total	1,749	1,940
Partnership and joint venture interests
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balances at beginning of period	3,403	0
Unrealized gains (losses)	118	0
Realized losses (gains)	187	0
Sales	0	0
Purchases	5,784	3,403
Transfers out of level 3	0
Transfers Into Level 3		0
Total	9,492	3,403
Real Estate Funds [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balances at beginning of period	18,156	16,257
Unrealized gains (losses)	543	1,894
Realized losses (gains)	0	(10)
Sales	(18,604)	0
Purchases	2	15
Transfers out of level 3	0
Transfers Into Level 3		0
Total	97	18,156
Hedge funds
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Balances at beginning of period	122	127
Unrealized gains (losses)	5	7
Realized losses (gains)	0	0
Sales	(14)	(12)
Purchases	0	0
Transfers out of level 3	0
Transfers Into Level 3		0
Total	$ 113	$ 122

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Amount of gain (loss) recognized in the income statement for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

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Amount of gain (loss) recognized in other comprehensive income (loss) for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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-Name Accounting Standards Codification

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Amount of purchases of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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-Publisher FASB

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Amount of sale of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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Amount of transfer of financial instrument classified as an asset into level 3 of the fair value hierarchy.

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Amount of transfers of financial instrument classified as an asset out of level 3 of the fair value hierarchy.

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Fair value of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

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