XML 41 R26.htm IDEA: XBRL DOCUMENT v3.7.0.1
FEES PAID BY THE FUND AND RELATED PARTY TRANSACTIONS (Details Textual) - USD ($)
 12 Months Ended
Dec. 31, 2016
Dec. 31, 2015
Dec. 31, 2014
Percentage Of Management Fee In Average Daily Total Net Assets 0.75%    
Estimated Investor Tax Reporting Cost $ 174,000 $ 140,000 $ 133,000
Percentage Of Fees and Other Waivers Expense 0.15%    
Expenses Write Off $ 190,095    
BNO [Member]      
Estimated Directors Fees and Expenses 11,565 10,575 9,150
BNO and Related Public Fund [Member]      
Estimated Directors Fees and Expenses $ 582,050 $ 569,303 $ 567,863