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Stock-Based Compensation Plans (Details) (Stock Options [Member], USD $)	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average fair value of stock options granted	$ 12.60	$ 15.77	$ 17.85
Expected volatility	76.74%	70.56%	72.56%
Expected life	5 years 0 months	5 years 6 months	6 years 0 months
Risk-free interest rate	0.84%	0.89%	2.30%
Expected dividend yield	0.00%	0.00%	0.00%

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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