v3.8.0.1

Schedule of Investments - Futures Contracts Purchased (Detail) | 9 Months Ended
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Sep. 30, 2017 USD ($) Contract
ProShares VIX Short-Term Futures ETF [Member] | Futures Contracts Purchased [Member] |  |
Schedule of Investments [Line Items] |  |
Unrealized Appreciation (Depreciation) | $ (18,329,321) |
ProShares VIX Short-Term Futures ETF [Member] | Futures Contracts Purchased [Member] | VIX Futures - CBOE, expires October 2017 [Member] |  |
Schedule of Investments [Line Items] |  |
Number of Contracts | Contract | 9,373 |
Notional Amount at Value | $ 109,429,775 |
Unrealized Appreciation (Depreciation) | $ (16,948,916) |
ProShares VIX Short-Term Futures ETF [Member] | Futures Contracts Purchased [Member] | VIX Futures - CBOE, expires November 2017 [Member] |  |
Schedule of Investments [Line Items] |  |
Number of Contracts | Contract | 6,252 |
Notional Amount at Value | $ 81,432,300 |
Unrealized Appreciation (Depreciation) | (1,380,405) |
ProShares VIX Mid-Term Futures ETF [Member] | Futures Contracts Purchased [Member] |  |
Schedule of Investments [Line Items] |  |
Unrealized Appreciation (Depreciation) | $ (1,941,640) |
ProShares VIX Mid-Term Futures ETF [Member] | Futures Contracts Purchased [Member] | VIX Futures - CBOE, expires January 2018 [Member] |  |
Schedule of Investments [Line Items] |  |
Number of Contracts | Contract | 582 |
Notional Amount at Value | $ 8,599,050 |
Unrealized Appreciation (Depreciation) | $ (697,300) |
ProShares VIX Mid-Term Futures ETF [Member] | Futures Contracts Purchased [Member] | VIX Futures - CBOE, expires February 2018 [Member] |  |
Schedule of Investments [Line Items] |  |
Number of Contracts | Contract | 971 |
Notional Amount at Value | $ 14,783,475 |
Unrealized Appreciation (Depreciation) | $ (652,385) |
ProShares VIX Mid-Term Futures ETF [Member] | Futures Contracts Purchased [Member] | VIX Futures - CBOE, expires March 2018 [Member] |  |
Schedule of Investments [Line Items] |  |
Number of Contracts | Contract | 971 |
Notional Amount at Value | $ 15,341,800 |
Unrealized Appreciation (Depreciation) | $ (547,765) |
ProShares VIX Mid-Term Futures ETF [Member] | Futures Contracts Purchased [Member] | VIX Futures - CBOE, expires April 2018 [Member] |  |
Schedule of Investments [Line Items] |  |
Number of Contracts | Contract | 388 |
Notional Amount at Value | $ 6,314,700 |
Unrealized Appreciation (Depreciation) | (44,190) |
ProShares Ultra VIX Short-Term Futures ETF [Member] | Futures Contracts Purchased [Member] |  |
Schedule of Investments [Line Items] |  |
Unrealized Appreciation (Depreciation) | $ (101,763,031) |
ProShares Ultra VIX Short-Term Futures ETF [Member] | Futures Contracts Purchased [Member] | VIX Futures - CBOE, expires October 2017 [Member] |  |
Schedule of Investments [Line Items] |  |
Number of Contracts | Contract | 52,495 |
Notional Amount at Value | $ 612,879,125 |
Unrealized Appreciation (Depreciation) | $ (93,982,537) |
ProShares Ultra VIX Short-Term Futures ETF [Member] | Futures Contracts Purchased [Member] | VIX Futures - CBOE, expires November 2017 [Member] |  |
Schedule of Investments [Line Items] |  |
Number of Contracts | Contract | 35,008 |
Notional Amount at Value | $ 455,979,200 |
Unrealized Appreciation (Depreciation) | (7,780,494) |
ProShares Ultra Bloomberg Crude Oil [Member] |  |
Schedule of Investments [Line Items] |  |
Unrealized Appreciation (Depreciation) | $ 40,796,900 | [1]
ProShares Ultra Bloomberg Crude Oil [Member] | Futures Contracts Purchased [Member] | WTI Crude Oil - NYMEX, expires November 2017 [Member] |  |
Schedule of Investments [Line Items] |  |
Number of Contracts | Contract | 5,855 |
Notional Amount at Value | $ 302,527,850 |
Unrealized Appreciation (Depreciation) | $ 13,817,653 |
ProShares UltraPro 3x Crude Oil ETF [Member] | Futures Contracts Purchased [Member] | WTI Crude Oil - NYMEX, expires November 2017 [Member] |  |
Schedule of Investments [Line Items] |  |
Number of Contracts | Contract | 440 |
Notional Amount at Value | $ 22,734,800 |
Unrealized Appreciation (Depreciation) | $ 1,272,779 |
ProShares Ultra Bloomberg Natural Gas [Member] | Futures Contracts Purchased [Member] | Natural Gas - NYMEX, expires November 2017 [Member] |  |
Schedule of Investments [Line Items] |  |
Number of Contracts | Contract | 3,396 |
Notional Amount at Value | $ 102,117,720 |
Unrealized Appreciation (Depreciation) | (971,690) |
ProShares Ultra Gold [Member] |  |
Schedule of Investments [Line Items] |  |
Unrealized Appreciation (Depreciation) | $ (8,453,427) | [1]
ProShares Ultra Gold [Member] | Futures Contracts Purchased [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) | 9,520 |
ProShares Ultra Silver [Member] |  |
Schedule of Investments [Line Items] |  |
Unrealized Appreciation (Depreciation) | $ (28,243,802) | [1]
ProShares Ultra Silver [Member] | Futures Contracts Purchased [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) |
[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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