v3.26.1
Agreements - Additional Information (Detail) - USD ($)
 3 Months Ended 6 Months Ended
Jun. 30, 2026
Jun. 30, 2026
Summary of Investment Holdings [Line Items]    
Ceiling for legal fees $ 100,000  
Percentage of annual NAV as limit to pay SEC registration fees incurred 0.021%  
Ceiling for per annum K-1 preparation and mailing fees against annual net assets of Fund 0.10%  
Leveraged Fund [Member]    
Summary of Investment Holdings [Line Items]    
Management Fee paid to sponsor, percent per annum of the average daily NAV of each Geared Fund   0.95%
GearedVix Funds [Member]    
Summary of Investment Holdings [Line Items]    
Management Fee paid to sponsor, percent per annum of the average daily NAV of each Geared Fund   0.95%
ProShares Short Euro [Member]    
Summary of Investment Holdings [Line Items]    
Management Fee paid to sponsor, percent per annum of the average daily NAV of each Geared Fund   0.95%
Matching VIX Funds [Member]    
Summary of Investment Holdings [Line Items]    
Management Fee paid to sponsor, percent per annum of the average daily NAV of each Geared Fund   0.85%