v2.4.1.9

Significant Accounting Policies - Cut-off Times and Times of Calculation of Funds' Final Net Asset Value for Creation and Redemption of Fund Shares (Detail) | 3 Months Ended
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Mar. 31, 2015
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 | March 31
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 | March 31
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 | March 31
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 | March 31
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 | March 31
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 | March 31
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 | March 31
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 | March 31
ProShares UltraShort Bloomberg Commodity [Member] |
Net Asset Value [Line Items] |
Create/Redeem Cut-off | 10:45 a.m.
NAV Calculation Time | 2:30 p.m.
NAV Calculation Date | March 31
ProShares Ultra Bloomberg Commodity [Member] |
Net Asset Value [Line Items] |
Create/Redeem Cut-off | 10:45 a.m.
NAV Calculation Time | 2:30 p.m.
NAV Calculation Date | March 31
ProShares Managed Futures Strategy [Member] |
Net Asset Value [Line Items] |
Create/Redeem Cut-off | 10:45 a.m.
NAV Calculation Time | 3:00 p.m.
NAV Calculation Date | March 31
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 | March 31
ProShares Ultra 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 | March 31
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 | March 31
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 | March 31
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 | March 31
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 | March 31
ProShares Ultra Yen [Member] |
Net Asset Value [Line Items] |
Create/Redeem Cut-off | 2:00 p.m.
NAV Calculation Time | 4:15 p.m.
NAV Calculation Date | March 31
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 | March 31
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 | March 31
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 | March 31
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 | March 31

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