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Stock-Based Compensation (Summary of Assumptions Used) (Details) (Stock Options, Common Stock)
3 Months Ended
Mar. 31, 2014
Mar. 31, 2013
Stock Options | Common Stock
   
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Expected life (years) 5 years 9 months 7 days 5 years 10 months 10 days
Risk-free interest rate 1.73% 0.77%
Expected volatility 63.80% 65.66%
Expected dividend yield 0.00% 0.00%