XML 28 R57.htm IDEA: XBRL DOCUMENT v2.4.0.6
Derivative Instruments (Details)
12 Months Ended
Dec. 31, 2012
Dec. 31, 2011
Fair value of warrants    
Expected dividend yield 0.00% 0.00%
Expected volatility 73.00% 79.00%
Maximum [Member]
   
Fair value of warrants    
Risk-free interest rate 0.35% 0.58%
Contractual term 2 years 10 months 24 days 3 years 10 months 24 days
Minimum [Member]
   
Fair value of warrants    
Risk-free interest rate 0.32% 0.52%
Contractual term 2 years 8 months 12 days 3 years 8 months 12 days