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Stock-Based Compensation (Valuation Assumptions) (Details) (Stock Only Stock Appreciation Rights (SOSARS))	3 Months Ended
	Mar. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected dividends	3.75%
Weighted average expected term (years)	6 years
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility (range)	58.00%
Risk free interest rate (range)	0.795%
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expected volatility (range)	59.00%
Risk free interest rate (range)	1.025%

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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