Stock Plans (Details 2) - Stock Option [Member] - $ / shares |
12 Months Ended | ||
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Dec. 31, 2015 |
Dec. 31, 2014 |
Dec. 31, 2013 |
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| Weighted Average Assumptions Used | |||
| Dividend yield | 1.10% | 1.10% | 1.40% |
| Expected volatility | 37.00% | 38.00% | 39.00% |
| Risk-free interest rate | 1.70% | 2.20% | 1.30% |
| Expected life of stock option (in years) | 6 years 7 months | 6 years 7 months | 6 years 3 months |
| Weighted-average fair value per option | $ 29.2 | $ 32.36 | $ 21.11 |
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- Definition Share based compensation arrangement by share based payment award fair value assumptions. No definition available.
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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 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 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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- 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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