Quarterly report pursuant to Section 13 or 15(d)

Concentrations (Details)

v2.4.0.8
Concentrations (Details)
3 Months Ended 6 Months Ended
Jun. 30, 2013
May 31, 2012
Feb. 29, 2012
Jun. 30, 2013
May 31, 2012
Dec. 31, 2012
Risks and Uncertainties [Abstract]            
Percentage of investments in securities of energy infrastructure companies in relation to aggregate assets 7.36%          
Term of contract 10 years          
Natural gas contract with Mowood, expiration year 2015          
Revenue related to the DOD contract 85.00% 85.00%   87.00% 89.00%  
Percentage of amounts due from the department of defense in relation to consolidated accounts receivable 85.00%     85.00%   84.00%
Percentage of payment to supplier of natural gas in relation to cost of sales 52.00% 31.00% 18.00%   41.00%