XML 51 R26.htm IDEA: XBRL DOCUMENT
v2.4.1.9

Fees Paid By The Fund And Related Party Transactions (Details Textual) (USD $) | 12 Months Ended
--- | ---
Dec. 31, 2014 | Dec. 31, 2013 | Dec. 31, 2012
Percentage Of Management Fee In Average Daily Total Net Assets | 0.75%bno_PercentageOfManagementFeeInAverageDailyTotalNetAssets |  |
Estimated Directors Fees and Expenses | $ 567,863 bno_EstimatedDirectorsFeesAndExpenses | $ 555,465 bno_EstimatedDirectorsFeesAndExpenses | $ 540,586 bno_EstimatedDirectorsFeesAndExpenses
Estimated Investor Tax Reporting Cost | 133,000 bno_EstimatedInvestorTaxReportingCost | 110,000 bno_EstimatedInvestorTaxReportingCost | 75,000 bno_EstimatedInvestorTaxReportingCost
Percentage Of Fees and Other Waivers Expense | 0.15%bno_PercentageOfFeesAndOtherWaiversExpense |  |
Expenses Write Off | 148,604 bno_ExpensesWriteOff |  |
BNO [Member] |  |  |
Estimated Directors Fees and Expenses | $ 9,150 bno_EstimatedDirectorsFeesAndExpenses / dei_LegalEntityAxis = bno_BNOMember | $ 9,012 bno_EstimatedDirectorsFeesAndExpenses / dei_LegalEntityAxis = bno_BNOMember | $ 9,844 bno_EstimatedDirectorsFeesAndExpenses / dei_LegalEntityAxis = bno_BNOMember

X
- Definition Estimated Directors Fees And Expenses. + References No definition available. + Details
Name: | bno_EstimatedDirectorsFeesAndExpenses
Namespace Prefix: | bno_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Estimated Investor Tax Reporting Cost. + References No definition available. + Details
Name: | bno_EstimatedInvestorTaxReportingCost
Namespace Prefix: | bno_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition expenses write off + References No definition available. + Details
Name: | bno_ExpensesWriteOff
Namespace Prefix: | bno_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition The percentage of fees and other waivers expense of maximum base points . + References No definition available. + Details
Name: | bno_PercentageOfFeesAndOtherWaiversExpense
Namespace Prefix: | bno_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Percentage of Management Fee In Average Daily Total Net Assets. + References No definition available. + Details
Name: | bno_PercentageOfManagementFeeInAverageDailyTotalNetAssets
Namespace Prefix: | bno_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | dei_LegalEntityAxis=bno_BNOMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |