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Share-Based Compensation (Fair Value Assumptions) (Details) (Stock Options [Member])	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2010
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk-free interest rate	1.23%	2.80%
Expected stock price volatility	65.00%	63.00%
Dividend yield	2.00%	1.40%
Expected life of options (years)	6 years	6 years 3 months

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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