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Stock-Based Compensation Plans (Weighted-Average Assumptions For The ESOP) (Details) (USD $)	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Stock-Based Compensation Plans [Abstract]
Dividend yield	2.60%	2.73%
Expected volatility	44.07%	40.39%
Risk-free interest rate	1.01%	2.24%
Expected term of options	4 years 11 days	4 years 18 days
Weighted-average grant-date fair value	$ 7.06	$ 8.36

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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