Stock Plans (Details 1) (Employee Stock Purchase Plan [Member], USD $)	6 Months Ended
Jun. 30, 2012
Employee Stock Purchase Plan [Member]
Schedule of stock options and employee stock purchase plan weighted-average assumptions
Expected dividends	0.00%
Exercise price	$ 16.24
Expected volatility	63.00%
Average risk-free interest rate	0.06%
Expected life/term (in years)	6 months
Fair value per share	$ 5.26

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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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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