Share-Based Compensation (Details 2) (USD $)	6 Months Ended	12 Months Ended
Jul. 28, 2012	Jan. 31, 2012
Aggregated information regarding stock options granted
Beginning balance, Weighted Average Remaining Contractual Life (in Years)	4 years 8 months 12 days	4 years 8 months 12 days
Granted, Number of Options	94,000
Granted, Weighted Average Exercise Price	$ 8.19
Exercised, Number of Options	(42,438)
Exercised, Weighted Average Exercise Price	$ 4.37
Expired or canceled, Number of Options	(40,056)
Expired or canceled, Weighted Average Exercise Price	$ 8.45
Ending balance, Number of Options	899,603	888,097
Ending balance, Weighted Average Exercise Price	$ 8.44	$ 8.27
Ending balance, Weighted Average Remaining Contractual Life (in Years)	4 years 8 months 12 days	4 years 8 months 12 days
Ending balance, Aggregated Intrinsic Value	$ 355,190	$ 547,874
Exercisable, Number of Options	736,203
Exercisable, Weighted Average Exercise Price	$ 8.58
Exercisable, Weighted Average Remaining Contractual Life (in years)	3 years 9 months 18 days
Exercisable, Aggregate Intrinsic Value	$ 305,966

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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Gross 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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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options of the plan that expired.

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

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