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Summary of Significant Accounting Policies (Details) (USD $)
In Thousands, except Per Share data, unless otherwise specified |
3 Months Ended | 6 Months Ended | ||
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Jul. 30, 2011
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Jul. 31, 2010
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Jul. 30, 2011
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Jul. 31, 2010
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| Fair value of stock option using a Black-Scholes valuation model | ||||
| Volatility rate | 54.20% | 58.80% | ||
| Average risk-free interest rate | 2.40% | 2.20% | ||
| Average expected life (in years) | 6.3 | 4.8 | ||
| Dividend yield | 0.00% | 0.00% | ||
| Summary of Significant Accounting Policies (Textuals) [Abstract] | ||||
| Number of shares granted in stock option | 124 | 745 | ||
| Weighted average fair value of stock option | $ 28.62 | $ 11.38 | ||
| Stock compensation expenses | $ 2,388 | $ 2,487 | $ 5,196 | $ 4,222 |
| Unrecognized compensation expense related to unvested options and restricted stock | $ 21,290 | $ 21,290 | ||
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- Definition
Summary Of Significant Accounting Policies.
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- Definition
As of the balance sheet date, the aggregate unrecognized cost of equity-based awards made to employees under equity-based compensation awards that have yet to vest. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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- Definition
The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The period of time an equity-based award is expected to be outstanding. An equity-based award's expected term is generally determined based on, among other factors, the instrument's contractual term and the effects of employees' expected exercise and post-vesting employment termination behavior. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The risk-free interest rate assumption that is used in valuing an option on its own shares. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
Net number of share options (or share units) granted during the period. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition
The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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