v3.10.0.1

Investments - Offsetting of Financial Assets and Liabilities (Detail) - USD ($) | Jun. 30, 2018 | Dec. 31, 2017
--- | --- | ---
ProShares Ultra Bloomberg Crude Oil [Member] | Swap Agreements [Member] |  |
Derivative [Line Items] |  |
Gross Amounts of Recognized Assets presented in the Statements of Financial Condition | $ 82,428,870 | $ 62,238,361
Gross Amounts Offset in the Statements of Financial Condition | 0 | 0
Net Amounts of Assets presented in the Statements of Financial Condition | 82,428,870 | 62,238,361
Gross Amounts Offset in the Statements of Financial Condition | 0 | 0
ProShares Ultra Euro [Member] | Foreign Currency Forward Contracts [Member] |  |
Derivative [Line Items] |  |
Gross Amounts of Recognized Assets presented in the Statements of Financial Condition |  | 321,609
Gross Amounts Offset in the Statements of Financial Condition | 0 | 0
Net Amounts of Assets presented in the Statements of Financial Condition |  | 321,609
Gross Amounts of Recognized Liabilities presented in the Statements of Financial Condition | 172,054 | 57,457
Gross Amounts Offset in the Statements of Financial Condition | 0 | 0
Net Amounts of Liabilities presented in the Statements of Financial Condition | 172,054 | 57,457
ProShares Ultra Gold [Member] | Forward Agreements [Member] |  |
Derivative [Line Items] |  |
Gross Amounts of Recognized Assets presented in the Statements of Financial Condition |  | 3,646,355
Gross Amounts Offset in the Statements of Financial Condition | 0 | 0
Net Amounts of Assets presented in the Statements of Financial Condition |  | 3,646,355
Gross Amounts of Recognized Liabilities presented in the Statements of Financial Condition | 7,152,896 |
Gross Amounts Offset in the Statements of Financial Condition | 0 | 0
Net Amounts of Liabilities presented in the Statements of Financial Condition | 7,152,896 |
ProShares Ultra Silver [Member] | Forward Agreements [Member] |  |
Derivative [Line Items] |  |
Gross Amounts of Recognized Assets presented in the Statements of Financial Condition |  | 21,735,334
Gross Amounts Offset in the Statements of Financial Condition | 0 | 0
Net Amounts of Assets presented in the Statements of Financial Condition |  | 21,735,334
Gross Amounts of Recognized Liabilities presented in the Statements of Financial Condition | 14,148,711 |
Gross Amounts Offset in the Statements of Financial Condition | 0 | 0
Net Amounts of Liabilities presented in the Statements of Financial Condition | 14,148,711 |
ProShares VIX Short-Term Futures ETF [Member] | Swap Agreements [Member] |  |
Derivative [Line Items] |  |
Gross Amounts of Recognized Assets presented in the Statements of Financial Condition | 1,302,919 |
Gross Amounts Offset in the Statements of Financial Condition | 0 |
Net Amounts of Assets presented in the Statements of Financial Condition | 1,302,919 |
Gross Amounts of Recognized Liabilities presented in the Statements of Financial Condition | 1,038,439 |
Gross Amounts Offset in the Statements of Financial Condition | 0 |
Net Amounts of Liabilities presented in the Statements of Financial Condition | 1,038,439 |
ProShares Ultra Yen [Member] | Foreign Currency Forward Contracts [Member] |  |
Derivative [Line Items] |  |
Gross Amounts of Recognized Assets presented in the Statements of Financial Condition | 311 |
Gross Amounts Offset in the Statements of Financial Condition | 0 | 0
Net Amounts of Assets presented in the Statements of Financial Condition | 311 |
Gross Amounts of Recognized Liabilities presented in the Statements of Financial Condition | 24,570 | 34,824
Gross Amounts Offset in the Statements of Financial Condition | 0 | 0
Net Amounts of Liabilities presented in the Statements of Financial Condition | 24,570 | 34,824
ProShares UltraShort Bloomberg Crude Oil [Member] | Swap Agreements [Member] |  |
Derivative [Line Items] |  |
Gross Amounts Offset in the Statements of Financial Condition | 0 | 0
Gross Amounts of Recognized Liabilities presented in the Statements of Financial Condition | 33,768,200 | 30,607,142
Gross Amounts Offset in the Statements of Financial Condition | 0 | 0
Net Amounts of Liabilities presented in the Statements of Financial Condition | 33,768,200 | 30,607,142
ProShares UltraShort Euro [Member] | Foreign Currency Forward Contracts [Member] |  |
Derivative [Line Items] |  |
Gross Amounts of Recognized Assets presented in the Statements of Financial Condition | 3,399,950 | 449,302
Gross Amounts Offset in the Statements of Financial Condition | 0 | 0
Net Amounts of Assets presented in the Statements of Financial Condition | 3,399,950 | 449,302
Gross Amounts of Recognized Liabilities presented in the Statements of Financial Condition |  | 6,793,571
Gross Amounts Offset in the Statements of Financial Condition | 0 | 0
Net Amounts of Liabilities presented in the Statements of Financial Condition |  | 6,793,571
ProShares UltraShort Gold [Member] | Forward Agreements [Member] |  |
Derivative [Line Items] |  |
Gross Amounts of Recognized Assets presented in the Statements of Financial Condition | 2,276,610 |
Gross Amounts Offset in the Statements of Financial Condition | 0 | 0
Net Amounts of Assets presented in the Statements of Financial Condition | 2,276,610 |
Gross Amounts of Recognized Liabilities presented in the Statements of Financial Condition |  | 1,488,259
Gross Amounts Offset in the Statements of Financial Condition | 0 | 0
Net Amounts of Liabilities presented in the Statements of Financial Condition |  | 1,488,259
ProShares UltraShort Silver [Member] | Forward Agreements [Member] |  |
Derivative [Line Items] |  |
Gross Amounts of Recognized Assets presented in the Statements of Financial Condition | 1,452,785 |
Gross Amounts Offset in the Statements of Financial Condition | 0 | 0
Net Amounts of Assets presented in the Statements of Financial Condition | 1,452,785 |
Gross Amounts of Recognized Liabilities presented in the Statements of Financial Condition |  | 1,716,163
Gross Amounts Offset in the Statements of Financial Condition | 0 | 0
Net Amounts of Liabilities presented in the Statements of Financial Condition |  | 1,716,163
ProShares UltraShort Yen [Member] | Foreign Currency Forward Contracts [Member] |  |
Derivative [Line Items] |  |
Gross Amounts of Recognized Assets presented in the Statements of Financial Condition | 751,278 | 1,568,997
Gross Amounts Offset in the Statements of Financial Condition | 0 | 0
Net Amounts of Assets presented in the Statements of Financial Condition | 751,278 | 1,568,997
Gross Amounts of Recognized Liabilities presented in the Statements of Financial Condition | 57,960 | 41,734
Gross Amounts Offset in the Statements of Financial Condition | 0 | 0
Net Amounts of Liabilities presented in the Statements of Financial Condition | $ 57,960 | $ 41,734

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