v2.4.0.6
Summary of Significant Accounting Policies (Stock Option Valuation Assumptions) (Details) (USD $)
12 Months Ended
Dec. 31, 2012
Dec. 31, 2011
Dec. 31, 2010
Accounting Policies [Abstract]      
Expected stock price volatility 77.11% 79.70% 72.90%
Annual dividend rate 0.00% 0.00% 0.00%
Risk-free interest rate 0.55% 0.40% 0.90%
Expected option life (in years) 4 years 3 months 18 days 3 years 4 years 3 months 18 days
Estimated fair value per share $ 3.04 $ 3.44 $ 4.67