v3.21.1

Investments - Fair Value of Derivative Instruments (Detail) - Not Designated as Hedging Instrument [Member] - USD ($) | Mar. 31, 2021 | Dec. 31, 2020
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Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Derivative asset not designated as hedging instrument, Unrealized Appreciation | [1] | $ 322,651,846 | $ 280,082,746
Derivative liability not accounted as hedging instrument, Unrealized Depreciation | [1] | 509,137,004 | 76,613,676
VIX Futures Contracts [Member] | Payable on open futures contracts, unrealized depreciation on swap agreements [Member] | ProShares Ultra VIX Short-Term Futures ETF [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Derivative liability not accounted as hedging instrument, Unrealized Depreciation | [1] | 332,928,249 | 48,549,473
VIX Futures Contracts [Member] | Payable on open futures contracts, unrealized depreciation on swap agreements [Member] | ProShares VIX Mid-Term Futures ETF [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Derivative liability not accounted as hedging instrument, Unrealized Depreciation | [1] | 9,410,288 | 1,281,531
VIX Futures Contracts [Member] | Payable on open futures contracts, unrealized depreciation on swap agreements [Member] | ProShares VIX Short-Term Futures ETF [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Derivative liability not accounted as hedging instrument, Unrealized Depreciation | [1] | 59,803,004 | 6,364,090
VIX Futures Contracts [Member] | Receivables on open futures contracts, unrealized appreciation on swap agreements [Member] | ProShares Short VIX Short-Term Futures ETF [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Derivative asset not designated as hedging instrument, Unrealized Appreciation | [1] | 50,470,675 | 8,348,783
VIX Futures Contracts [Member] | Receivables on open futures contracts, unrealized appreciation on swap agreements [Member] | ProShares VIX Mid-Term Futures ETF [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Derivative asset not designated as hedging instrument, Unrealized Appreciation | [1] |  | 147,915
Commodity Contracts [Member] | Payable on open futures contracts and/or unrealized depreciation on swap agreements [Member] | ProShares UltraShort Bloomberg Crude Oil [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Derivative liability not accounted as hedging instrument, Unrealized Depreciation | [1] | 9,469,307 | 14,636,813
Commodity Contracts [Member] | Payable on open futures contracts and/or unrealized depreciation on swap agreements [Member] | ProShares UltraShort Gold [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Derivative liability not accounted as hedging instrument, Unrealized Depreciation | [1] | 685,467 | 465,658
Commodity Contracts [Member] | Payable on open futures contracts and/or unrealized depreciation on swap agreements [Member] | ProShares UltraShort Silver [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Derivative liability not accounted as hedging instrument, Unrealized Depreciation | [1] |  | 3,417,637
Commodity Contracts [Member] | Payable on open futures contracts and/or unrealized depreciation on swap agreements [Member] | ProShares Ultra Bloomberg Crude Oil [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Derivative liability not accounted as hedging instrument, Unrealized Depreciation | [1] | 41,086,983 |
Commodity Contracts [Member] | Payable on open futures contracts and/or unrealized depreciation on swap agreements [Member] | ProShares Ultra Bloomberg Natural Gas [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Derivative liability not accounted as hedging instrument, Unrealized Depreciation | [1] | 11,300,062 |
Commodity Contracts [Member] | Payable on open futures contracts and/or unrealized depreciation on swap agreements [Member] | ProShares Ultra Silver [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Derivative liability not accounted as hedging instrument, Unrealized Depreciation | [1] | 43,822,824 |
Commodity Contracts [Member] | Receivables on open futures contracts and/or unrealized appreciation on swap agreements [Member] | ProShares UltraShort Bloomberg Crude Oil [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Derivative asset not designated as hedging instrument, Unrealized Appreciation | [1] | 469,128 |
Commodity Contracts [Member] | Receivables on open futures contracts and/or unrealized appreciation on swap agreements [Member] | ProShares UltraShort Bloomberg Natural Gas [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Derivative asset not designated as hedging instrument, Unrealized Appreciation | [1] | 16,272,857 | 379,310
Commodity Contracts [Member] | Receivables on open futures contracts and/or unrealized appreciation on swap agreements [Member] | ProShares UltraShort Gold [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Derivative asset not designated as hedging instrument, Unrealized Appreciation | [1] | 39,145 |
Commodity Contracts [Member] | Receivables on open futures contracts and/or unrealized appreciation on swap agreements [Member] | ProShares UltraShort Silver [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Derivative asset not designated as hedging instrument, Unrealized Appreciation | [1] | 4,048,127 |
Commodity Contracts [Member] | Receivables on open futures contracts and/or unrealized appreciation on swap agreements [Member] | ProShares Ultra Bloomberg Crude Oil [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Derivative asset not designated as hedging instrument, Unrealized Appreciation | [1] | 238,887,300 | 162,806,234
Commodity Contracts [Member] | Receivables on open futures contracts and/or unrealized appreciation on swap agreements [Member] | ProShares Ultra Bloomberg Natural Gas [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Derivative asset not designated as hedging instrument, Unrealized Appreciation | [1] |  | 6,500,721
Commodity Contracts [Member] | Receivables on open futures contracts and/or unrealized appreciation on swap agreements [Member] | ProShares Ultra Gold [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Derivative asset not designated as hedging instrument, Unrealized Appreciation | [1] | 6,553,555 | 7,787,854
Commodity Contracts [Member] | Receivables on open futures contracts and/or unrealized appreciation on swap agreements [Member] | ProShares Ultra Silver [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Derivative asset not designated as hedging instrument, Unrealized Appreciation | [1] |  | 93,942,878
Foreign Exchange Contracts [Member] | Unrealized Depreciation on Foreign Currency Forward Contracts, and/or Payable on Open Futures Contracts [Member] | ProShares Short Euro [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Derivative liability not accounted as hedging instrument, Unrealized Depreciation | [1] |  | 44,626
Foreign Exchange Contracts [Member] | Unrealized Depreciation on Foreign Currency Forward Contracts, and/or Payable on Open Futures Contracts [Member] | ProShares Ultra Euro [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Derivative liability not accounted as hedging instrument, Unrealized Depreciation |  | 226,734 | 367
Foreign Exchange Contracts [Member] | Unrealized Depreciation on Foreign Currency Forward Contracts, and/or Payable on Open Futures Contracts [Member] | ProShares UltraShort Australian Dollar [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Derivative liability not accounted as hedging instrument, Unrealized Depreciation | [1] |  | 138,950
Foreign Exchange Contracts [Member] | Unrealized Depreciation on Foreign Currency Forward Contracts, and/or Payable on Open Futures Contracts [Member] | ProShares Ultra Yen [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Derivative liability not accounted as hedging instrument, Unrealized Depreciation |  | 192,043 | 148
Foreign Exchange Contracts [Member] | Unrealized Depreciation on Foreign Currency Forward Contracts, and/or Payable on Open Futures Contracts [Member] | ProShares UltraShort Euro [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Derivative liability not accounted as hedging instrument, Unrealized Depreciation |  | 181,875 | 1,142,409
Foreign Exchange Contracts [Member] | Unrealized Depreciation on Foreign Currency Forward Contracts, and/or Payable on Open Futures Contracts [Member] | ProShares UltraShort Yen [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Derivative liability not accounted as hedging instrument, Unrealized Depreciation |  | 30,168 | 571,974
Foreign Exchange Contracts [Member] | Unrealized Appreciation on Foreign Currency Forward Contracts, and/or Receivables on Open Futures Contracts [Member] | ProShares Short Euro [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Derivative asset not designated as hedging instrument, Unrealized Appreciation | [1] | 33,928 |
Foreign Exchange Contracts [Member] | Unrealized Appreciation on Foreign Currency Forward Contracts, and/or Receivables on Open Futures Contracts [Member] | ProShares Ultra Euro [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Derivative asset not designated as hedging instrument, Unrealized Appreciation |  | 4,330 | 89,103
Foreign Exchange Contracts [Member] | Unrealized Appreciation on Foreign Currency Forward Contracts, and/or Receivables on Open Futures Contracts [Member] | ProShares UltraShort Australian Dollar [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Derivative asset not designated as hedging instrument, Unrealized Appreciation | [1] | 67,102 |
Foreign Exchange Contracts [Member] | Unrealized Appreciation on Foreign Currency Forward Contracts, and/or Receivables on Open Futures Contracts [Member] | ProShares Ultra Yen [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Derivative asset not designated as hedging instrument, Unrealized Appreciation |  | 3,041 | 67,235
Foreign Exchange Contracts [Member] | Unrealized Appreciation on Foreign Currency Forward Contracts, and/or Receivables on Open Futures Contracts [Member] | ProShares UltraShort Euro [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Derivative asset not designated as hedging instrument, Unrealized Appreciation |  | 3,436,568 | 5,705
Foreign Exchange Contracts [Member] | Unrealized Appreciation on Foreign Currency Forward Contracts, and/or Receivables on Open Futures Contracts [Member] | ProShares UltraShort Yen [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Derivative asset not designated as hedging instrument, Unrealized Appreciation |  | $ 2,366,090 | $ 7,008
[1] | Includes cumulative appreciation (depreciation) of futures contracts as reported in the Schedule of Investments. Only current day’s variation margin is reported within the Statements of Financial Condition in receivable/payable on open futures.

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