Future Minimum Lease Payments for Noncancelable Operating and Capital Leases (Detail) (USD $)	Aug. 31, 2012
Capital Lease Expense [Member]
Leases [Line Items]
2013	$ 297
2014	45
2015	45
2016	43
2017	29
Thereafter	12
Total minimum lease payments	471
Less: amounts representing interest	(48)
Net minimum lease payments	423
Operating Lease Expense [Member]
Leases [Line Items]
2013	3,273
2014	2,341
2015	1,263
2016	669
2017	307
Thereafter
Total minimum lease payments	$ 7,853

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Amount of minimum lease payments for capital leases.

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Amount of minimum lease payments maturing in the third fiscal year following the latest fiscal year for capital leases.

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Present value of minimum lease payments for capital leases net of executory costs, including amounts paid by the lessee to the lessor for insurance, maintenance and taxes.

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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.

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