v3.8.0.1

Schedule of Investments - Swap Agreements (Detail) | 9 Months Ended
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Sep. 30, 2017 USD ($) | [1]
ProShares UltraShort Bloomberg Crude Oil [Member] |  |
Schedule of Investments [Line Items] |  |
Unrealized Appreciation (Depreciation) | $ (13,678,377) |
ProShares UltraShort Bloomberg Crude Oil [Member] | Swap Agreement with Citibank, N.A. based on Bloomberg Crude Oil Sub-Index [Member] |  |
Schedule of Investments [Line Items] |  |
Rate Paid (Received) | (0.18%) | [2]
Termination Date | Oct. 05, 2017 |
Notional Amount at Value | $ (149,040,494) | [3]
Unrealized Appreciation (Depreciation) | $ (6,092,070) |
ProShares UltraShort Bloomberg Crude Oil [Member] | Swap Agreement with Goldman Sachs International based on Bloomberg Crude Oil Sub-Index [Member] |  |
Schedule of Investments [Line Items] |  |
Rate Paid (Received) | (0.25%) | [2]
Termination Date | Oct. 05, 2017 |
Notional Amount at Value | $ (109,832,549) | [3]
Unrealized Appreciation (Depreciation) | $ (3,900,635) |
ProShares UltraShort Bloomberg Crude Oil [Member] | Swap Agreement with Societe Generale based on Bloomberg Crude Oil Sub-Index [Member] |  |
Schedule of Investments [Line Items] |  |
Rate Paid (Received) | (0.25%) | [2]
Termination Date | Oct. 05, 2017 |
Notional Amount at Value | $ (12,927,229) | [3]
Unrealized Appreciation (Depreciation) | $ (514,835) |
ProShares UltraShort Bloomberg Crude Oil [Member] | Swap Agreement with UBS AG based on Bloomberg Crude Oil Sub-Index [Member] |  |
Schedule of Investments [Line Items] |  |
Rate Paid (Received) | (0.25%) | [2]
Termination Date | Oct. 05, 2017 |
Notional Amount at Value | $ (106,765,884) | [3]
Unrealized Appreciation (Depreciation) | (3,170,837) |
ProShares Ultra Bloomberg Crude Oil [Member] |  |
Schedule of Investments [Line Items] |  |
Unrealized Appreciation (Depreciation) | $ 40,796,900 |
ProShares Ultra Bloomberg Crude Oil [Member] | Swap Agreement with Citibank, N.A. based on Bloomberg Crude Oil Sub-Index [Member] |  |
Schedule of Investments [Line Items] |  |
Rate Paid (Received) | 0.18% | [2]
Termination Date | Oct. 05, 2017 |
Notional Amount at Value | $ 332,458,695 | [3]
Unrealized Appreciation (Depreciation) | $ 13,855,515 |
ProShares Ultra Bloomberg Crude Oil [Member] | Swap Agreement with Goldman Sachs International based on Bloomberg Crude Oil Sub-Index [Member] |  |
Schedule of Investments [Line Items] |  |
Rate Paid (Received) | 0.25% | [2]
Termination Date | Oct. 05, 2017 |
Notional Amount at Value | $ 242,703,814 | [3]
Unrealized Appreciation (Depreciation) | $ 11,965,958 |
ProShares Ultra Bloomberg Crude Oil [Member] | Swap Agreement with Societe Generale based on Bloomberg Crude Oil Sub-Index [Member] |  |
Schedule of Investments [Line Items] |  |
Rate Paid (Received) | 0.25% | [2]
Termination Date | Oct. 05, 2017 |
Notional Amount at Value | $ 115,090,880 | [3]
Unrealized Appreciation (Depreciation) | $ 4,548,744 |
ProShares Ultra Bloomberg Crude Oil [Member] | Swap Agreement with UBS AG based on Bloomberg Crude Oil Sub-Index [Member] |  |
Schedule of Investments [Line Items] |  |
Rate Paid (Received) | 0.25% | [2]
Termination Date | Oct. 05, 2017 |
Notional Amount at Value | $ 251,436,908 | [3]
Unrealized Appreciation (Depreciation) | $ 10,426,683 |
[1] | The positions and counterparties herein are as of September 30, 2017. The Funds continually evaluate different counterparties for their transactions and counterparties are subject to change. New counterparties can be added at any time.
[2] | Reflects the floating financing rate, as of September 30, 2017, on the notional amount of the swap agreement paid to the counterparty or received from the counterparty, excluding any commissions.
[3] | For swap agreements, a positive amount represents "long" exposure to the benchmark index. A negative amount represents "short" exposure to the benchmark index.

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