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Stock-Based Employee Compensation (Details 7) (1989 Employee Stock Purchase Plan [Member], Employee stock purchase plan [Member])
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12 Months Ended | ||
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Feb. 28, 2014
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Feb. 28, 2013
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Feb. 29, 2012
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1989 Employee Stock Purchase Plan [Member] | Employee stock purchase plan [Member]
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| Weighted average assumptions to estimate fair value of equity instruments using Black-Scholes option-pricing model | |||
| Expected life | 0 years 6 months | 0 years 6 months | 0 years 6 months |
| Expected volatility | 24.30% | 41.80% | 30.40% |
| Risk-free interest rate | 0.10% | 0.10% | 0.20% |
| Expected dividend yield | 0.00% | 0.00% | 0.00% |
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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
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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- 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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