Shareholders' Equity - Stock Option (Incentive and Nonqualified) Activity (Detail) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
May 04, 2013
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Outstanding at Feb 2, 2013, Shares	2,388,048
Granted, shares
Exercised, shares	(4,500)
Forfeited or expired shares	(36,593)
Outstanding at May 4, 2013, Shares	2,346,955
Shares, vested and expected to vest at May 4, 2013	2,304,447
Shares, exercisable at May 4, 2013	1,387,264
Weighted-Average Exercise Price, Outstanding at February 2, 2013	$ 5.66
Granted, Weighted-Average Exercise Price
Exercised, Weighted-Average Exercise Price	$ 1.64
Forfeited or expired, Weighted-Average Exercise Price	$ 10.58
Weighted-Average Exercise Price Outstanding at May 4, 2013	$ 5.59
Vested and expected to vest at May 4, 2013, Weighted-Average Exercise Price	$ 5.63
Exercisable at May 4, 2013, Weighted-Average Exercise Price	$ 6.78
Outstanding at May 4 ,2013, Weighted-Average Remaining Contractual Term	3 years 4 months 24 days
Vested and expected to vest at May 4, 2013, Weighted-Average Remaining Contractual Term	3 years 3 months 18 days
Exercisable at May 4, 2013, Weighted-Average Remaining Contractual Term	3 years
Outstanding at May 4, 2013, Aggregate Intrinsic Value	$ 180
Vested and expected to vest at May 4, 2013, Aggregate Intrinsic Value	173
Exercisable at May 4, 2013, Aggregate Intrinsic Value	$ 138

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

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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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