Quarterly report pursuant to Section 13 or 15(d)

Fair Value (Details Textual)

v2.4.0.6
Fair Value (Details Textual) (CO2 Solutions [Member], USD $)
3 Months Ended 12 Months Ended
Mar. 31, 2013
Dec. 31, 2012
Dec. 31, 2011
CO2 Solutions [Member]
     
Subsidiary or Equity Method Investee [Line Items]      
Number of common shares fair value 10,000,000    
Fair value of investment in CO2 solutions's common stock $ 900,000 $ 600,000  
Unrealized gain (loss) on investment 200,000   47,000
Unrealized gain (loss) on investment, tax 100,000    
Investment impairment recorded $ 800,000 $ 800,000