Income Taxes - Reconciliation of Beginning and Ending Amount of Unrecognized Tax Benefits (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Aug. 31, 2013	Aug. 31, 2012
Income Tax Disclosure [Abstract]
Unrecognized tax benefits at beginning of year	$ 1,058	$ 1,220
Additions for tax positions related to prior years	134	112
Additions for tax positions related to current year	90	62
Reductions due to lapse of applicable statute of limitations	(576)	(336)
Unrecognized tax benefits at end of year	$ 706	$ 1,058

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Amount of unrecognized tax benefits pertaining to uncertain tax positions taken in tax returns.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Unrecognized Tax Benefit

-URI http://asc.fasb.org/extlink&oid=6527854

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

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-Section 50

-Paragraph 15A

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- Definition

Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

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-Paragraph 15A

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Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

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Amount of decrease in unrecognized tax benefits resulting from lapses of applicable statutes of limitations.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 740

-SubTopic 10

-Section 50

-Paragraph 15A

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