| Stock-Based Compensation (Schedule Of Weighted Average Assumptions) (Details) (Stock Option [Member], USD $) | 3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
| Jun. 30, 2014 | Jun. 30, 2013 | Jun. 30, 2014 | Jun. 30, 2013 | |
| Stock Option [Member] | ||||
| Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | ||||
| Expected term, years | 7 years 9 months 25 days | 7 years 7 days | 4 years 8 months 15 days | 4 years 8 months 19 days | 
| Expected stock price volatility | 28.63% | 28.54% | 27.67% | 30.80% | 
| Risk-free interest rate | 2.29% | 1.55% | 1.21% | 0.69% | 
| Expected dividend yield | 1.33% | 1.44% | 1.33% | 1.63% | 
| Weighted average grant date fair value (in dollars per share) | $ 25.54 | $ 16.45 | $ 17.52 | $ 12.31 | 
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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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- Details 
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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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