Summary of Stock Option Activity (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended	12 Months Ended
Nov. 21, 2012	Aug. 29, 2012
Shares Under Fixed Options
Outstanding beginning balance	1,175,224
Granted	109,335
Exercised	0
Forfeited/Expired	(281,565)
Outstanding ending balance	1,002,994	1,175,224
Exercisable ending balance	642,895
Weighted-Average Exercise Price
Outstanding beginning balance	$ 6.31
Granted	$ 5.95
Exercised	$ 0
Forfeited/Expired	$ 0
Outstanding ending balance	$ 5.17	$ 6.31
Exercisable ending balance	$ 5.25
Weighted-Average Remaining Contractual Term (Years)
Outstanding, weighted-average remaining contractual term	5 years 1 month 6 days	3 years 9 months 18 days
Exercisable, weighted-average remaining contractual term	4 years 4 months 24 days
Aggregate Intrinsic Value
Outstanding, beginning balance	$ 1,456
Granted	0
Exercised	0
Forfeited/Expired	0
Outstanding, ending balance	1,527	1,456
Exercisable ending balance	$ 1,055

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Share Based Compensation Arrangement By Share Based Payment Award Options Forfeitures And Expirations In Period Intrinsic Value

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The total accumulated difference between fair values of underlying shares on dates of exercise and exercise price on options which were exercised (or share units converted) into shares during the reporting period under the plan.

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For presentations that combine terminations, the number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan or that expired.

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Weighted average price of options that were either forfeited or expired.

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Net number of share options (or share units) granted during the period.

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of options outstanding.

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The number of shares reserved for issuance under stock option agreements awarded under the plan that validly exist and are outstanding as of the balance sheet date, including vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Number of share options (or share units) exercised during the current period.

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