Employee Stock And Incentive Plan (Assumptions Used In The Pricing Model - Stock Options) (Details) (Stock Options [Member], USD $)	12 Months Ended
Dec. 31, 2010 years	Dec. 31, 2009 years
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected term (years)	6.0	5.3
Risk-free interest rate	2.80%	2.20%
Expected volatility	26.70%	31.30%
Dividend yield	3.30%	3.00%
Grant date fair value per option	$ 3.49	$ 4.37

The period of time an equity-based award is expected to be outstanding. An equity-based award's expected term is generally determined based on, among other factors, the instrument's contractual term and the effects of employees' expected exercise and post-vesting employment termination behavior.

+ References+ Details

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.

+ References+ Details