v3.8.0.1

Schedule of Investments - Futures Contracts Sold (Detail) | 9 Months Ended
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Sep. 30, 2017 USD ($) Contract
ProShares Short VIX Short-Term Futures ETF [Member] | Futures Contracts Sold [Member] |  |
Schedule of Investments [Line Items] |  |
Unrealized Appreciation (Depreciation) | $ 94,244,035 |
ProShares Short VIX Short-Term Futures ETF [Member] | Futures Contracts Sold [Member] | VIX Futures - CBOE, expires October 2017 [Member] |  |
Schedule of Investments [Line Items] |  |
Number of Contracts | Contract | 51,224 |
Notional Amount at Value | $ 598,040,200 |
Unrealized Appreciation (Depreciation) | $ 86,369,735 |
ProShares Short VIX Short-Term Futures ETF [Member] | Futures Contracts Sold [Member] | VIX Futures - CBOE, expires November 2017 [Member] |  |
Schedule of Investments [Line Items] |  |
Number of Contracts | Contract | 34,126 |
Notional Amount at Value | $ 444,491,150 |
Unrealized Appreciation (Depreciation) | 7,874,300 |
ProShares UltraShort Bloomberg Crude Oil [Member] |  |
Schedule of Investments [Line Items] |  |
Unrealized Appreciation (Depreciation) | $ (13,678,377) | [1]
ProShares UltraShort Bloomberg Crude Oil [Member] | Futures Contracts Sold [Member] | WTI Crude Oil - NYMEX, expires November 2017 [Member] |  |
Schedule of Investments [Line Items] |  |
Number of Contracts | Contract | 1,894 |
Notional Amount at Value | $ 97,862,980 |
Unrealized Appreciation (Depreciation) | $ (5,367,489) |
Pro Shares UltraPro 3X Short Crude Oil ETF [Member] | Futures Contracts Sold [Member] | WTI Crude Oil - NYMEX, expires November 2017 [Member] |  |
Schedule of Investments [Line Items] |  |
Number of Contracts | Contract | 916 |
Notional Amount at Value | $ 47,329,720 |
Unrealized Appreciation (Depreciation) | $ (2,423,370) |
ProShares UltraShort Bloomberg Natural Gas [Member] | Futures Contracts Sold [Member] | Natural Gas - NYMEX, expires November 2017 [Member] |  |
Schedule of Investments [Line Items] |  |
Number of Contracts | Contract | 394 |
Notional Amount at Value | $ 11,847,580 |
Unrealized Appreciation (Depreciation) | 348,521 |
ProShares UltraShort Gold [Member] |  |
Schedule of Investments [Line Items] |  |
Unrealized Appreciation (Depreciation) | $ 2,961,605 | [1]
ProShares UltraShort Gold [Member] | Futures Contracts Sold [Member] | Gold Futures - COMEX, expires December 2017 [Member] |  |
Schedule of Investments [Line Items] |  |
Number of Contracts | Contract | 2 |
Notional Amount at Value | $ 256,960 |
Unrealized Appreciation (Depreciation) | (9,540) |
ProShares UltraShort Silver [Member] |  |
Schedule of Investments [Line Items] |  |
Unrealized Appreciation (Depreciation) | $ 2,152,433 | [1]
ProShares UltraShort Silver [Member] | Futures Contracts Sold [Member] | Silver Futures - COMEX, expires December 2017 [Member] |  |
Schedule of Investments [Line Items] |  |
Number of Contracts | Contract | 2 |
Notional Amount at Value | $ 166,760 |
Unrealized Appreciation (Depreciation) | $ 4,940 |
ProShares Short Euro [Member] | Futures Contracts Sold [Member] | Euro Fx Currency Futures - CME, expires December 2017 [Member] |  |
Schedule of Investments [Line Items] |  |
Number of Contracts | Contract | 55 |
Notional Amount at Value | $ 8,156,844 |
Unrealized Appreciation (Depreciation) | $ 106,206 |
ProShares UltraShort Australian Dollar [Member] | Futures Contracts Sold [Member] | Australian Dollar Fx Currency Futures - CME, expires December 2017 [Member] |  |
Schedule of Investments [Line Items] |  |
Number of Contracts | Contract | 232 |
Notional Amount at Value | $ 18,179,520 |
Unrealized Appreciation (Depreciation) | $ 379,490 |
[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.

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