v3.8.0.1

Significant Accounting Policies - Cut-off Times and Times of Calculation of Funds' Final Net Asset Value for Creation and Redemption of Fund Shares (Detail) | 9 Months Ended
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Sep. 30, 2017
ProShares UltraShort Silver [Member] |
Net Asset Value [Line Items] |
Create/Redeem Cut-off | 6:30 a.m.
NAV Calculation Time | 7:00 a.m.
NAV Calculation Date | September 30, 2017
ProShares Ultra Silver [Member] |
Net Asset Value [Line Items] |
Create/Redeem Cut-off | 6:30 a.m.
NAV Calculation Time | 7:00 a.m.
NAV Calculation Date | September 30, 2017
ProShares UltraShort Gold [Member] |
Net Asset Value [Line Items] |
Create/Redeem Cut-off | 9:30 a.m.
NAV Calculation Time | 10:00 a.m.
NAV Calculation Date | September 30, 2017
ProShares Ultra Gold [Member] |
Net Asset Value [Line Items] |
Create/Redeem Cut-off | 9:30 a.m.
NAV Calculation Time | 10:00 a.m.
NAV Calculation Date | September 30, 2017
ProShares UltraShort Bloomberg Crude Oil [Member] |
Net Asset Value [Line Items] |
Create/Redeem Cut-off | 2:00 p.m.
NAV Calculation Time | 2:30 p.m.
NAV Calculation Date | September 30, 2017
ProShares Ultra Bloomberg Crude Oil [Member] |
Net Asset Value [Line Items] |
Create/Redeem Cut-off | 2:00 p.m.
NAV Calculation Time | 2:30 p.m.
NAV Calculation Date | September 30, 2017
Pro Shares UltraPro 3X Short Crude Oil ETF [Member] |
Net Asset Value [Line Items] |
Create/Redeem Cut-off | 2:00 p.m.
NAV Calculation Time | 2:30 p.m.
NAV Calculation Date | September 30, 2017
ProShares UltraPro 3x Crude Oil ETF [Member] |
Net Asset Value [Line Items] |
Create/Redeem Cut-off | 2:00 p.m.
NAV Calculation Time | 2:30 p.m.
NAV Calculation Date | September 30, 2017
ProShares UltraShort Bloomberg Natural Gas [Member] |
Net Asset Value [Line Items] |
Create/Redeem Cut-off | 2:00 p.m.
NAV Calculation Time | 2:30 p.m.
NAV Calculation Date | September 30, 2017
ProShares Ultra Bloomberg Natural Gas [Member] |
Net Asset Value [Line Items] |
Create/Redeem Cut-off | 2:00 p.m.
NAV Calculation Time | 2:30 p.m.
NAV Calculation Date | September 30, 2017
ProShares UltraShort Australian Dollar [Member] |
Net Asset Value [Line Items] |
Create/Redeem Cut-off | 3:00 p.m.
NAV Calculation Time | 4:00 p.m.
NAV Calculation Date | September 30, 2017
ProShares Short Euro [Member] |
Net Asset Value [Line Items] |
Create/Redeem Cut-off | 3:00 p.m.
NAV Calculation Time | 4:00 p.m.
NAV Calculation Date | September 30, 2017
ProShares UltraShort Euro [Member] |
Net Asset Value [Line Items] |
Create/Redeem Cut-off | 3:00 p.m.
NAV Calculation Time | 4:00 p.m.
NAV Calculation Date | September 30, 2017
ProShares Ultra Euro [Member] |
Net Asset Value [Line Items] |
Create/Redeem Cut-off | 3:00 p.m.
NAV Calculation Time | 4:00 p.m.
NAV Calculation Date | September 30, 2017
ProShares UltraShort Yen [Member] |
Net Asset Value [Line Items] |
Create/Redeem Cut-off | 3:00 p.m.
NAV Calculation Time | 4:00 p.m.
NAV Calculation Date | September 30, 2017
ProShares Ultra Yen [Member] |
Net Asset Value [Line Items] |
Create/Redeem Cut-off | 3:00 p.m.
NAV Calculation Time | 4:00 p.m.
NAV Calculation Date | September 30, 2017
ProShares VIX Short-Term Futures ETF [Member] |
Net Asset Value [Line Items] |
Create/Redeem Cut-off | 2:00 p.m.
NAV Calculation Time | 4:15 p.m.
NAV Calculation Date | September 30, 2017
ProShares Short VIX Short-Term Futures ETF [Member] |
Net Asset Value [Line Items] |
Create/Redeem Cut-off | 2:00 p.m.
NAV Calculation Time | 4:15 p.m.
NAV Calculation Date | September 30, 2017
ProShares Ultra VIX Short-Term Futures ETF [Member] |
Net Asset Value [Line Items] |
Create/Redeem Cut-off | 2:00 p.m.
NAV Calculation Time | 4:15 p.m.
NAV Calculation Date | September 30, 2017
ProShares VIX Mid-Term Futures ETF [Member] |
Net Asset Value [Line Items] |
Create/Redeem Cut-off | 2:00 p.m.
NAV Calculation Time | 4:15 p.m.
NAV Calculation Date | September 30, 2017

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