v3.8.0.1

Investments - Offsetting of Financial Assets and Liabilities (Detail) - USD ($) | Sep. 30, 2017 | Dec. 31, 2016
--- | --- | ---
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 | 13,678,377 | 12,206,881
Gross Amounts Offset in the Statements of Financial Condition | 0 | 0
Net Amounts of Liabilities presented in the Statements of Financial Condition | 13,678,377 | 12,206,881
ProShares UltraShort Gold [Member] | Forward Agreements [Member] |  |
Derivative [Line Items] |  |
Gross Amounts of Recognized Assets presented in the Statements of Financial Condition | 2,961,605 | 3,033,566
Gross Amounts Offset in the Statements of Financial Condition | 0 | 0
Net Amounts of Assets presented in the Statements of Financial Condition | 2,961,605 | 3,033,566
Gross Amounts Offset in the Statements of Financial Condition | 0 | 0
ProShares UltraShort Silver [Member] | Forward Agreements [Member] |  |
Derivative [Line Items] |  |
Gross Amounts of Recognized Assets presented in the Statements of Financial Condition | 2,152,433 | 1,384,246
Gross Amounts Offset in the Statements of Financial Condition | 0 | 0
Net Amounts of Assets presented in the Statements of Financial Condition | 2,152,433 | 1,384,246
Gross Amounts Offset in the Statements of Financial Condition | 0 | 0
ProShares UltraShort Euro [Member] | Foreign Currency Forward Contracts [Member] |  |
Derivative [Line Items] |  |
Gross Amounts of Recognized Assets presented in the Statements of Financial Condition | 4,465,552 | 16,519,070
Gross Amounts Offset in the Statements of Financial Condition | 0 | 0
Net Amounts of Assets presented in the Statements of Financial Condition | 4,465,552 | 16,519,070
Gross Amounts of Recognized Liabilities presented in the Statements of Financial Condition | 565,859 | 356,139
Gross Amounts Offset in the Statements of Financial Condition | 0 | 0
Net Amounts of Liabilities presented in the Statements of Financial Condition | 565,859 | 356,139
ProShares UltraShort Yen [Member] | Foreign Currency Forward Contracts [Member] |  |
Derivative [Line Items] |  |
Gross Amounts of Recognized Assets presented in the Statements of Financial Condition | 9,817,020 | 16,870,357
Gross Amounts Offset in the Statements of Financial Condition | 0 | 0
Net Amounts of Assets presented in the Statements of Financial Condition | 9,817,020 | 16,870,357
Gross Amounts of Recognized Liabilities presented in the Statements of Financial Condition | 570,141 | 125,420
Gross Amounts Offset in the Statements of Financial Condition | 0 | 0
Net Amounts of Liabilities presented in the Statements of Financial Condition | 570,141 | 125,420
ProShares Ultra Bloomberg Crude Oil [Member] | Swap Agreements [Member] |  |
Derivative [Line Items] |  |
Gross Amounts of Recognized Assets presented in the Statements of Financial Condition | 40,796,900 | 55,358,571
Gross Amounts Offset in the Statements of Financial Condition | 0 | 0
Net Amounts of Assets presented in the Statements of Financial Condition | 40,796,900 | 55,358,571
Gross Amounts Offset in the Statements of Financial Condition | 0 | 0
ProShares Ultra Gold [Member] | Forward 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 | 8,453,427 | 4,431,107
Gross Amounts Offset in the Statements of Financial Condition | 0 | 0
Net Amounts of Liabilities presented in the Statements of Financial Condition | 8,453,427 | 4,431,107
ProShares Ultra Silver [Member] | Forward 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 | 28,243,802 | 20,976,189
Gross Amounts Offset in the Statements of Financial Condition | 0 | 0
Net Amounts of Liabilities presented in the Statements of Financial Condition | 28,243,802 | 20,976,189
ProShares Ultra Euro [Member] | Foreign Currency Forward Contracts [Member] |  |
Derivative [Line Items] |  |
Gross Amounts of Recognized Assets presented in the Statements of Financial Condition | 82,079 | 2,548
Gross Amounts Offset in the Statements of Financial Condition | 0 | 0
Net Amounts of Assets presented in the Statements of Financial Condition | 82,079 | 2,548
Gross Amounts of Recognized Liabilities presented in the Statements of Financial Condition | 291,439 | 576,558
Gross Amounts Offset in the Statements of Financial Condition | 0 | 0
Net Amounts of Liabilities presented in the Statements of Financial Condition | 291,439 | 576,558
ProShares Ultra Yen [Member] | Foreign Currency Forward Contracts [Member] |  |
Derivative [Line Items] |  |
Gross Amounts of Recognized Assets presented in the Statements of Financial Condition | 12,351 | 379
Gross Amounts Offset in the Statements of Financial Condition | 0 | 0
Net Amounts of Assets presented in the Statements of Financial Condition | 12,351 | 379
Gross Amounts of Recognized Liabilities presented in the Statements of Financial Condition | 407,660 | 342,455
Gross Amounts Offset in the Statements of Financial Condition | 0 | 0
Net Amounts of Liabilities presented in the Statements of Financial Condition | $ 407,660 | $ 342,455

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