Commitments and Contingencies - Schedule of Future Minimum Noncancellable Operating Lease Payments (Details) (USD $) In Thousands, unless otherwise specified	Aug. 31, 2014
Schedule of Future Minimum Payments on Operating Lease Commitments
2015	$ 101,326
2016	74,489
2017	65,973
2018	50,685
2019	34,190
Thereafter	103,091
Total minimum future lease payments	429,754
Rail Cars
Schedule of Future Minimum Payments on Operating Lease Commitments
2015	24,329
2016	23,286
2017	21,926
2018	17,027
2019	11,682
Thereafter	11,261
Total minimum future lease payments	109,511
Vehicles
Schedule of Future Minimum Payments on Operating Lease Commitments
2015	15,344
2016	10,568
2017	7,761
2018	5,309
2019	2,406
Thereafter	1,791
Total minimum future lease payments	43,179
Equipment and Other
Schedule of Future Minimum Payments on Operating Lease Commitments
2015	61,653
2016	40,635
2017	36,286
2018	28,349
2019	20,102
Thereafter	90,039
Total minimum future lease payments	$ 277,064

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Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 20

-Section 50

-Paragraph 2

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6453985&loc=d3e41502-112717

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 10

-Section 55

-Paragraph 40

-Subparagraph (Note 3)

-URI http://asc.fasb.org/extlink&oid=6584154&loc=d3e38371-112697

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due 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 required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due 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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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due 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 required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due 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 required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due 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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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due 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.

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