v2.4.1.9
Offering Costs - Additional Information (Detail)
3 Months Ended
Mar. 31, 2015
Organization And Offering Costs [Line Items]  
Offering costs, amortization period 12 months
Managed Futures Fund [Member]  
Organization And Offering Costs [Line Items]  
Sponsor reimbursement of organization and offering costs, maximum for each Leveraged Fund 0.75%ck0001415311_PercentageOfAverageDailyNavOfFund
/ us-gaap_InvestmentTypeAxis
= ck0001415311_ManagedFuturesFundMember