XML 53 R27.htm IDEA: XBRL DOCUMENT v2.4.0.6
FINANCIAL HIGHLIGHTS (Per Unit Performance Data and Other Supplemental Financial Data) (Details) (USD $)
 3 Months Ended
Mar. 31, 2013
Mar. 31, 2012
Nov. 18, 2009
Per Unit Operating Performance:      
Net asset value, beginning of period $ 17.23 $ 21.21 $ 50.00
Total income (loss) $ 2.09 $ (4.79)  
Total expenses $ (0.04) $ (0.05)  
Net increase (decrease) in net asset value $ 2.05 $ (4.84)  
Net asset value, end of period $ 19.28 $ 16.37 $ 50.00
Total Return 11.90% (22.82%)  
Ratios to Average Net Assets      
Total income (loss) 11.51% (28.65%)  
Management fees 0.75% 0.75%  
Total expenses excluding management fees 0.34% [1] 0.52% [1]  
Expenses waived (0.13%) [1] (0.28%) [1]  
Net expenses excluding management fees 0.21% [1] 0.24% [1]  
Net income (loss) 11.27% (28.89%)  
[1] Annualized