v3.21.1

Agreements - Additional Information (Detail) | 3 Months Ended
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Mar. 31, 2021 USD ($)
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] |
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] |
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] |
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] |
Investment Holdings [Line Items] |
Management Fee paid to sponsor, percent per annum of the average daily NAV of each Geared Fund | 0.85%

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- Definition Ceiling for fee paid to administrative and legal facilitators. + References No definition available. + Details
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- Definition Ceiling for ongoing SEC registration fee of percentage of annual Nav. + References No definition available. + Details
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- Details
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- Details
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- Details
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