Stock-Based Compensation (Schedule Of Assumptions Used To Estimate Value Of Each Option Award) (Details) - Stock Options [Member]	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Assumptions used to estimate value of each option award
Expected volatility (as a percent)	28.40%	25.90%	27.70%
Expected dividend yield (as a percent)	0.00%	0.00%	0.00%
Expected life (in years)	5 years	6 years 3 months 18 days	6 years 3 months 18 days
Risk-free interest rate, minimum (as a percent)	2.49%	2.63%	1.83%
Risk-free interest rate, maximum (as a percent)		2.94%	2.29%

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.

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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.

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- Definition

The maximum risk-free interest rate assumption that is used in valuing an option on its own shares.

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No definition available.

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- Definition

The minimum risk-free interest rate assumption that is used in valuing an option on its own shares.

+ References

No definition available.

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- Definition

Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 718
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