Quarterly report pursuant to Section 13 or 15(d)

Concentrations (Details)

Concentrations (Details)
3 Months Ended
Mar. 31, 2014
Mar. 31, 2013
Dec. 31, 2013
Risks and Uncertainties [Abstract]      
Percentage of investments in securities of energy infrastructure companies in relation to aggregate assets 7.00%    
Term of contract 10 years    
Natural gas contract with Mowood, expiration year 2015    
Revenue related to the DOD contract 91.00% 89.00%  
Percentage of amounts due from the department of defense in relation to consolidated accounts receivable 88.00%   91.00%
Percentage of payment to supplier of natural gas in relation to cost of sales 77.00% 48.00%