Summary of Significant Accounting Policies - Black-Scholes Valuation Model Weighted-Average Assumptions (Detail) - Employee Stock Option [Member] |
3 Months Ended | |
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Apr. 29, 2017 |
Apr. 30, 2016 |
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| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||
| Volatility rate | 31.00% | 35.00% |
| Average risk-free interest rate | 1.60% | 1.20% |
| Average expected life (in years) | 3 years 6 months | 3 years 6 months |
| Dividend yield | 0.00% | 0.00% |
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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 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 Weighted average expected volatility rate of share-based compensation awards. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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- Definition Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Details
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