Equity (Details) (USD $)
In Millions, except Share data, unless otherwise specified
6 Months Ended
Jun. 30, 2012
Feb. 15, 2012
Dec. 31, 2011
Equity (Textual) [Abstract]      
Common stock, shares authorized 100,000,000 100,000,000 30,000,000
Common stock, par value $ 0.01 $ 0.01 $ 0.01
Preferred stock, shares authorized 10,000,000 10,000,000  
Preferred stock, par value $ 0.01 $ 0.01  
Conversion price adjustment one preferred share into one and one-half common shares    
Automatic Conversion of Shares [Member]
     
Conversion of Stock [Line Items]      
Percentage of Outstanding Shares of Preferred Shareholders Required 66.00%    
Minimum post-offering valuation on a fully diluted basis required $ 150    
Minimum Proceeds Required $ 25