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Schedule of Option Pricing Model Assumptions (Details) (USD $)
12 Months Ended
Dec. 31, 2012
Dec. 31, 2011
Dec. 31, 2010
Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract]      
Expected volatility rate minimum 50.00% 50.00%  
Expected volatility rate maximum 70.00% 60.00%  
Expected volatility rate     60.00%
Dividend yield $ 0 $ 0 $ 0
Risk-free interest rate minimum 0.62% 0.87% 1.64%
Risk-free interest rate maximum 1.20% 2.31% 2.27%
Expected life minimum 4 years 4 years 4 months 5 years 8 months
Expected life maximum 4 years 3 months 4 years 10 months 6 years 6 months