v3.10.0.1

Investments - Gross Amounts Not Offset in Statements of Financial Condition (Detail) - USD ($) | Jun. 30, 2018 | Dec. 31, 2017
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ProShares Ultra Bloomberg Crude Oil [Member] | Goldman Sachs International [Member] |  |
Derivative [Line Items] |  |
Amounts of Recognized Assets presented in the Statements of Financial Condition | $ 21,365,763 | $ 16,654,031
Financial Instruments for the Benefit of (the Funds) / the Counterparties | (20,159,696) | (14,861,090)
Net Amounts of Assets presented in the Statements of Financial Condition | 1,206,067 | 1,792,941
ProShares Ultra Bloomberg Crude Oil [Member] | UBS AG [Member] |  |
Derivative [Line Items] |  |
Amounts of Recognized Assets presented in the Statements of Financial Condition | 21,864,163 | 16,764,919
Financial Instruments for the Benefit of (the Funds) / the Counterparties | (20,658,539) | (15,477,566)
Net Amounts of Assets presented in the Statements of Financial Condition | 1,205,624 | 1,287,353
ProShares Ultra Bloomberg Crude Oil [Member] | Citibank N.A. [Member] |  |
Derivative [Line Items] |  |
Amounts of Recognized Assets presented in the Statements of Financial Condition | 29,027,266 | 19,815,892
Net Amounts of Assets presented in the Statements of Financial Condition | 29,027,266 | 19,815,892
ProShares Ultra Bloomberg Crude Oil [Member] | Societe Generale S.A. [Member] |  |
Derivative [Line Items] |  |
Amounts of Recognized Assets presented in the Statements of Financial Condition | 8,999,126 | 9,003,519
Financial Instruments for the Benefit of (the Funds) / the Counterparties | (8,942,433) | (8,525,505)
Net Amounts of Assets presented in the Statements of Financial Condition | 56,693 | 478,014
ProShares Ultra Bloomberg Crude Oil [Member] | RBC. NA [Member] |  |
Derivative [Line Items] |  |
Amounts of Recognized Assets presented in the Statements of Financial Condition | 1,172,552 |
Net Amounts of Assets presented in the Statements of Financial Condition | 1,172,552 |
ProShares Ultra Euro [Member] | Goldman Sachs International [Member] |  |
Derivative [Line Items] |  |
Amounts of Recognized Assets presented in the Statements of Financial Condition |  | 102,424
Net Amounts of Assets presented in the Statements of Financial Condition |  | 102,424
Amounts of Recognized Assets presented in the Statements of Financial Condition | (77,986) |
Cash Collateral for the Benefit of (the Funds) / the Counterparties | 77,986 |
ProShares Ultra Euro [Member] | UBS AG [Member] |  |
Derivative [Line Items] |  |
Amounts of Recognized Assets presented in the Statements of Financial Condition |  | 161,728
Net Amounts of Assets presented in the Statements of Financial Condition |  | 161,728
Amounts of Recognized Assets presented in the Statements of Financial Condition | (94,068) |
Cash Collateral for the Benefit of (the Funds) / the Counterparties | 94,068 |
ProShares Ultra Gold [Member] | Goldman Sachs International [Member] |  |
Derivative [Line Items] |  |
Amounts of Recognized Assets presented in the Statements of Financial Condition |  | 969,501
Financial Instruments for the Benefit of (the Funds) / the Counterparties |  | (967,678)
Cash Collateral for the Benefit of (the Funds) / the Counterparties |  | (1,823)
Amounts of Recognized Assets presented in the Statements of Financial Condition | (1,977,494) |
Financial Instruments for the Benefit of (the Funds) / the Counterparties | 1,977,494 |
ProShares Ultra Gold [Member] | UBS AG [Member] |  |
Derivative [Line Items] |  |
Amounts of Recognized Assets presented in the Statements of Financial Condition |  | 945,225
Financial Instruments for the Benefit of (the Funds) / the Counterparties |  | (945,225)
Amounts of Recognized Assets presented in the Statements of Financial Condition | (1,952,388) |
Financial Instruments for the Benefit of (the Funds) / the Counterparties | 1,952,388 |
ProShares Ultra Gold [Member] | Citibank N.A. [Member] |  |
Derivative [Line Items] |  |
Amounts of Recognized Assets presented in the Statements of Financial Condition |  | 1,513,310
Net Amounts of Assets presented in the Statements of Financial Condition |  | 1,513,310
Amounts of Recognized Assets presented in the Statements of Financial Condition | (2,546,835) |
Financial Instruments for the Benefit of (the Funds) / the Counterparties | 2,546,835 |
ProShares Ultra Gold [Member] | Societe Generale S.A. [Member] |  |
Derivative [Line Items] |  |
Amounts of Recognized Assets presented in the Statements of Financial Condition |  | 218,319
Net Amounts of Assets presented in the Statements of Financial Condition |  | 218,319
Amounts of Recognized Assets presented in the Statements of Financial Condition | (676,179) |
Financial Instruments for the Benefit of (the Funds) / the Counterparties | 676,179 |
ProShares Ultra Silver [Member] | Goldman Sachs International [Member] |  |
Derivative [Line Items] |  |
Amounts of Recognized Assets presented in the Statements of Financial Condition |  | 5,873,080
Financial Instruments for the Benefit of (the Funds) / the Counterparties |  | (4,903,696)
Net Amounts of Assets presented in the Statements of Financial Condition |  | 969,384
Amounts of Recognized Assets presented in the Statements of Financial Condition | (4,075,705) |
Financial Instruments for the Benefit of (the Funds) / the Counterparties | 732,705 |
Cash Collateral for the Benefit of (the Funds) / the Counterparties | 3,343,000 |
ProShares Ultra Silver [Member] | UBS AG [Member] |  |
Derivative [Line Items] |  |
Amounts of Recognized Assets presented in the Statements of Financial Condition |  | 5,898,693
Financial Instruments for the Benefit of (the Funds) / the Counterparties |  | (4,930,596)
Net Amounts of Assets presented in the Statements of Financial Condition |  | 968,097
Amounts of Recognized Assets presented in the Statements of Financial Condition | (3,722,182) |
Financial Instruments for the Benefit of (the Funds) / the Counterparties | 3,722,182 |
ProShares Ultra Silver [Member] | Citibank N.A. [Member] |  |
Derivative [Line Items] |  |
Amounts of Recognized Assets presented in the Statements of Financial Condition |  | 7,201,744
Net Amounts of Assets presented in the Statements of Financial Condition |  | 7,201,744
Amounts of Recognized Assets presented in the Statements of Financial Condition | (4,560,857) |
Cash Collateral for the Benefit of (the Funds) / the Counterparties | 4,560,857 |
ProShares Ultra Silver [Member] | Societe Generale S.A. [Member] |  |
Derivative [Line Items] |  |
Amounts of Recognized Assets presented in the Statements of Financial Condition |  | 2,761,817
Financial Instruments for the Benefit of (the Funds) / the Counterparties |  | (2,516,153)
Net Amounts of Assets presented in the Statements of Financial Condition |  | 245,664
Amounts of Recognized Assets presented in the Statements of Financial Condition | (1,789,967) |
Financial Instruments for the Benefit of (the Funds) / the Counterparties | 1,789,967 |
ProShares VIX Short-Term Futures ETF [Member] | Goldman Sachs International [Member] |  |
Derivative [Line Items] |  |
Amounts of Recognized Assets presented in the Statements of Financial Condition | (1,038,439) |
Cash Collateral for the Benefit of (the Funds) / the Counterparties | 1,038,439 |
ProShares VIX Short-Term Futures ETF [Member] | Deutsche Bank [Member] |  |
Derivative [Line Items] |  |
Amounts of Recognized Assets presented in the Statements of Financial Condition | 1,302,919 |
Cash Collateral for the Benefit of (the Funds) / the Counterparties | (1,302,919) |
ProShares Ultra Yen [Member] | Goldman Sachs International [Member] |  |
Derivative [Line Items] |  |
Amounts of Recognized Assets presented in the Statements of Financial Condition | (11,885) | (17,410)
Financial Instruments for the Benefit of (the Funds) / the Counterparties |  | 17,410
Cash Collateral for the Benefit of (the Funds) / the Counterparties | 11,885 |
Net Amounts of Liabilities presented in the Statements of Financial Condition |  |
ProShares Ultra Yen [Member] | UBS AG [Member] |  |
Derivative [Line Items] |  |
Amounts of Recognized Assets presented in the Statements of Financial Condition | (12,374) | (17,414)
Financial Instruments for the Benefit of (the Funds) / the Counterparties |  | 17,414
Cash Collateral for the Benefit of (the Funds) / the Counterparties | 12,374 |
Net Amounts of Liabilities presented in the Statements of Financial Condition |  |
ProShares UltraShort Bloomberg Crude Oil [Member] | Goldman Sachs International [Member] |  |
Derivative [Line Items] |  |
Amounts of Recognized Assets presented in the Statements of Financial Condition | (8,713,478) | (9,242,398)
Financial Instruments for the Benefit of (the Funds) / the Counterparties | 8,713,478 | 9,242,398
Net Amounts of Liabilities presented in the Statements of Financial Condition |  |
ProShares UltraShort Bloomberg Crude Oil [Member] | UBS AG [Member] |  |
Derivative [Line Items] |  |
Amounts of Recognized Assets presented in the Statements of Financial Condition | (8,567,454) | (9,287,467)
Financial Instruments for the Benefit of (the Funds) / the Counterparties | 6,870,954 | 9,287,467
Cash Collateral for the Benefit of (the Funds) / the Counterparties | 1,696,500 |
Net Amounts of Liabilities presented in the Statements of Financial Condition |  |
ProShares UltraShort Bloomberg Crude Oil [Member] | Citibank N.A. [Member] |  |
Derivative [Line Items] |  |
Amounts of Recognized Assets presented in the Statements of Financial Condition | (11,914,957) | (10,173,164)
Financial Instruments for the Benefit of (the Funds) / the Counterparties | 11,914,957 | 10,173,164
Net Amounts of Liabilities presented in the Statements of Financial Condition |  |
ProShares UltraShort Bloomberg Crude Oil [Member] | Societe Generale S.A. [Member] |  |
Derivative [Line Items] |  |
Amounts of Recognized Assets presented in the Statements of Financial Condition | (3,627,720) | (1,904,113)
Financial Instruments for the Benefit of (the Funds) / the Counterparties | 3,627,720 | 1,904,113
Net Amounts of Liabilities presented in the Statements of Financial Condition |  |
ProShares UltraShort Bloomberg Crude Oil [Member] | RBC. NA [Member] |  |
Derivative [Line Items] |  |
Amounts of Recognized Assets presented in the Statements of Financial Condition | (944,591) |
Net Amounts of Liabilities presented in the Statements of Financial Condition | (944,591) |
ProShares UltraShort Euro [Member] | Goldman Sachs International [Member] |  |
Derivative [Line Items] |  |
Amounts of Recognized Assets presented in the Statements of Financial Condition | 1,779,254 |
Financial Instruments for the Benefit of (the Funds) / the Counterparties | (1,779,254) |
Amounts of Recognized Assets presented in the Statements of Financial Condition |  | (3,297,612)
Financial Instruments for the Benefit of (the Funds) / the Counterparties |  | 259,612
Cash Collateral for the Benefit of (the Funds) / the Counterparties |  | 3,038,000
Net Amounts of Liabilities presented in the Statements of Financial Condition |  |
ProShares UltraShort Euro [Member] | UBS AG [Member] |  |
Derivative [Line Items] |  |
Amounts of Recognized Assets presented in the Statements of Financial Condition | 1,620,696 |
Financial Instruments for the Benefit of (the Funds) / the Counterparties | (1,620,696) |
Amounts of Recognized Assets presented in the Statements of Financial Condition |  | (3,046,657)
Financial Instruments for the Benefit of (the Funds) / the Counterparties |  | 3,046,657
Net Amounts of Liabilities presented in the Statements of Financial Condition |  |
ProShares UltraShort Gold [Member] | Goldman Sachs International [Member] |  |
Derivative [Line Items] |  |
Amounts of Recognized Assets presented in the Statements of Financial Condition | 615,252 |
Financial Instruments for the Benefit of (the Funds) / the Counterparties | (577,828) |
Net Amounts of Assets presented in the Statements of Financial Condition | 37,424 |
Amounts of Recognized Assets presented in the Statements of Financial Condition |  | (428,358)
Financial Instruments for the Benefit of (the Funds) / the Counterparties |  | 428,358
Net Amounts of Liabilities presented in the Statements of Financial Condition |  |
ProShares UltraShort Gold [Member] | UBS AG [Member] |  |
Derivative [Line Items] |  |
Amounts of Recognized Assets presented in the Statements of Financial Condition | 621,773 |
Financial Instruments for the Benefit of (the Funds) / the Counterparties | (581,161) |
Net Amounts of Assets presented in the Statements of Financial Condition | 40,612 |
Amounts of Recognized Assets presented in the Statements of Financial Condition |  | (378,414)
Financial Instruments for the Benefit of (the Funds) / the Counterparties |  | 378,414
Net Amounts of Liabilities presented in the Statements of Financial Condition |  |
ProShares UltraShort Gold [Member] | Citibank N.A. [Member] |  |
Derivative [Line Items] |  |
Amounts of Recognized Assets presented in the Statements of Financial Condition | 793,507 |
Net Amounts of Assets presented in the Statements of Financial Condition | 793,507 |
Amounts of Recognized Assets presented in the Statements of Financial Condition |  | (554,559)
Financial Instruments for the Benefit of (the Funds) / the Counterparties |  | 554,559
Net Amounts of Liabilities presented in the Statements of Financial Condition |  |
ProShares UltraShort Gold [Member] | Societe Generale S.A. [Member] |  |
Derivative [Line Items] |  |
Amounts of Recognized Assets presented in the Statements of Financial Condition | 246,078 |
Financial Instruments for the Benefit of (the Funds) / the Counterparties | (246,078) |
Amounts of Recognized Assets presented in the Statements of Financial Condition |  | (126,928)
Financial Instruments for the Benefit of (the Funds) / the Counterparties |  | 126,928
Net Amounts of Liabilities presented in the Statements of Financial Condition |  |
ProShares UltraShort Silver [Member] | Goldman Sachs International [Member] |  |
Derivative [Line Items] |  |
Amounts of Recognized Assets presented in the Statements of Financial Condition | 402,097 |
Financial Instruments for the Benefit of (the Funds) / the Counterparties | (349,222) |
Net Amounts of Assets presented in the Statements of Financial Condition | 52,875 |
Amounts of Recognized Assets presented in the Statements of Financial Condition |  | (486,240)
Cash Collateral for the Benefit of (the Funds) / the Counterparties |  | 486,240
Net Amounts of Liabilities presented in the Statements of Financial Condition |  |
ProShares UltraShort Silver [Member] | UBS AG [Member] |  |
Derivative [Line Items] |  |
Amounts of Recognized Assets presented in the Statements of Financial Condition | 384,979 |
Net Amounts of Assets presented in the Statements of Financial Condition | 384,979 |
Amounts of Recognized Assets presented in the Statements of Financial Condition |  | (482,025)
Financial Instruments for the Benefit of (the Funds) / the Counterparties |  | 482,025
Net Amounts of Liabilities presented in the Statements of Financial Condition |  |
ProShares UltraShort Silver [Member] | Citibank N.A. [Member] |  |
Derivative [Line Items] |  |
Amounts of Recognized Assets presented in the Statements of Financial Condition | 582,164 |
Net Amounts of Assets presented in the Statements of Financial Condition | 582,164 |
Amounts of Recognized Assets presented in the Statements of Financial Condition |  | (632,593)
Financial Instruments for the Benefit of (the Funds) / the Counterparties |  | 632,593
Net Amounts of Liabilities presented in the Statements of Financial Condition |  |
ProShares UltraShort Silver [Member] | Societe Generale S.A. [Member] |  |
Derivative [Line Items] |  |
Amounts of Recognized Assets presented in the Statements of Financial Condition | 83,545 |
Net Amounts of Assets presented in the Statements of Financial Condition | 83,545 |
Amounts of Recognized Assets presented in the Statements of Financial Condition |  | (115,305)
Financial Instruments for the Benefit of (the Funds) / the Counterparties |  | 115,305
Net Amounts of Liabilities presented in the Statements of Financial Condition |  |
ProShares UltraShort Yen [Member] | Goldman Sachs International [Member] |  |
Derivative [Line Items] |  |
Amounts of Recognized Assets presented in the Statements of Financial Condition | 348,163 | 821,317
Financial Instruments for the Benefit of (the Funds) / the Counterparties |  | (810,030)
Net Amounts of Assets presented in the Statements of Financial Condition | 348,163 | 11,287
ProShares UltraShort Yen [Member] | UBS AG [Member] |  |
Derivative [Line Items] |  |
Amounts of Recognized Assets presented in the Statements of Financial Condition | 345,155 | 705,946
Cash Collateral for the Benefit of (the Funds) / the Counterparties |  | $ (705,946)
Net Amounts of Assets presented in the Statements of Financial Condition | $ 345,155 |

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