v2.4.0.8

Investments - Fair Value of Derivative Instruments (Detail) (USD $) | Mar. 31, 2014 | Dec. 31, 2013
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Derivative Instruments, Gain (Loss) [Line Items] |  |
Derivative asset not designated as hedging instrument, Unrealized Appreciation | $ 38,486,246 | $ 49,932,144
Derivative liability not designated as hedging instrument, Unrealized Depreciation | 122,164,235 | 80,537,134
Commodity Contracts [Member] | Receivables on Open Futures Contracts, Unrealized Appreciation on Swap and/ or Forwards Agreements [Member] | ProShares UltraShort DJ-UBS Commodity [Member] |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Derivative asset not designated as hedging instrument, Unrealized Appreciation | 102,269 |
Commodity Contracts [Member] | Receivables on Open Futures Contracts, Unrealized Appreciation on Swap and/ or Forwards Agreements [Member] | ProShares UltraShort DJ-UBS Crude Oil [Member] |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Derivative asset not designated as hedging instrument, Unrealized Appreciation | 71,219 |
Commodity Contracts [Member] | Receivables on Open Futures Contracts, Unrealized Appreciation on Swap and/ or Forwards Agreements [Member] | ProShares UltraShort Gold [Member] |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Derivative asset not designated as hedging instrument, Unrealized Appreciation | 8,548,622 | 5,647,573
Commodity Contracts [Member] | Receivables on Open Futures Contracts, Unrealized Appreciation on Swap and/ or Forwards Agreements [Member] | ProShares UltraShort Silver [Member] |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Derivative asset not designated as hedging instrument, Unrealized Appreciation | 7,747,910 | 14,200
Commodity Contracts [Member] | Receivables on Open Futures Contracts, Unrealized Appreciation on Swap and/ or Forwards Agreements [Member] | ProShares Ultra DJ-UBS Commodity [Member] |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Derivative asset not designated as hedging instrument, Unrealized Appreciation |  | 15,078
Commodity Contracts [Member] | Receivables on Open Futures Contracts, Unrealized Appreciation on Swap and/ or Forwards Agreements [Member] | ProShares Ultra DJ-UBS Crude Oil [Member] |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Derivative asset not designated as hedging instrument, Unrealized Appreciation | 3,069,265 | 2,584,554
Commodity Contracts [Member] | Receivables on Open Futures Contracts, Unrealized Appreciation on Swap and/ or Forwards Agreements [Member] | ProShares UltraShort DJ-UBS Natural Gas [Member] |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Derivative asset not designated as hedging instrument, Unrealized Appreciation | 4,479,320 | 1,042,300
Commodity Contracts [Member] | Payable on Open Futures Contracts, Unrealized Depreciation on Swap and/or Forward Agreements [Member] | ProShares UltraShort DJ-UBS Commodity [Member] |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Derivative liability not designated as hedging instrument, Unrealized Depreciation | 114,128 |
Commodity Contracts [Member] | Payable on Open Futures Contracts, Unrealized Depreciation on Swap and/or Forward Agreements [Member] | ProShares UltraShort DJ-UBS Crude Oil [Member] |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Derivative liability not designated as hedging instrument, Unrealized Depreciation | 7,028,464 | 3,565,673
Commodity Contracts [Member] | Payable on Open Futures Contracts, Unrealized Depreciation on Swap and/or Forward Agreements [Member] | ProShares Ultra DJ-UBS Natural Gas [Member] |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Derivative liability not designated as hedging instrument, Unrealized Depreciation |  | 3,656,539
Commodity Contracts [Member] | Payable on Open Futures Contracts, Unrealized Depreciation on Swap and/or Forward Agreements [Member] | ProShares UltraShort Gold [Member] |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Derivative liability not designated as hedging instrument, Unrealized Depreciation | 12,026,932 |
Commodity Contracts [Member] | Payable on Open Futures Contracts, Unrealized Depreciation on Swap and/or Forward Agreements [Member] | ProShares UltraShort Silver [Member] |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Derivative liability not designated as hedging instrument, Unrealized Depreciation | 58,143,691 | 2,227,857
Commodity Contracts [Member] | Payable on Open Futures Contracts, Unrealized Depreciation on Swap and/or Forward Agreements [Member] | ProShares Short Euro [Member] |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Derivative liability not designated as hedging instrument, Unrealized Depreciation | 1,851,411 |
Commodity Contracts [Member] | Payable on Open Futures Contracts, Unrealized Depreciation on Swap and/or Forward Agreements [Member] | ProShares Ultra DJ-UBS Commodity [Member] |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Derivative liability not designated as hedging instrument, Unrealized Depreciation |  | 27,665
Commodity Contracts [Member] | Payable on Open Futures Contracts, Unrealized Depreciation on Swap and/or Forward Agreements [Member] | ProShares Ultra Gold [Member] |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Derivative liability not designated as hedging instrument, Unrealized Depreciation |  | 6,827,534
Commodity Contracts [Member] | Payable on Open Futures Contracts, Unrealized Depreciation on Swap and/or Forward Agreements [Member] | ProShares Ultra Silver [Member] |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Derivative liability not designated as hedging instrument, Unrealized Depreciation |  | 2,507,080
Foreign Exchange Contracts [Member] | Unrealized Depreciation on Foreign Currency Forward Contracts and Payable on Open Futures Contracts [Member] | ProShares Short Euro [Member] |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Derivative liability not designated as hedging instrument, Unrealized Depreciation |  | 33,231
Foreign Exchange Contracts [Member] | Unrealized Depreciation on Foreign Currency Forward Contracts and Payable on Open Futures Contracts [Member] | ProShares UltraShort Australian Dollar [Member] |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Derivative liability not designated as hedging instrument, Unrealized Depreciation | 1,221,879 |
Foreign Exchange Contracts [Member] | Unrealized Depreciation on Foreign Currency Forward Contracts and Payable on Open Futures Contracts [Member] | ProShares UltraShort Euro [Member] |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Derivative liability not designated as hedging instrument, Unrealized Depreciation | 3,724,310 | 13,899,858
Foreign Exchange Contracts [Member] | Unrealized Depreciation on Foreign Currency Forward Contracts and Payable on Open Futures Contracts [Member] | ProShares UltraShort Yen [Member] |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Derivative liability not designated as hedging instrument, Unrealized Depreciation | 1,275,150 | 1,930,884
Foreign Exchange Contracts [Member] | Unrealized Depreciation on Foreign Currency Forward Contracts and Payable on Open Futures Contracts [Member] | ProShares Ultra Australian Dollar [Member] |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Derivative liability not designated as hedging instrument, Unrealized Depreciation |  | 118,220
Foreign Exchange Contracts [Member] | Unrealized Depreciation on Foreign Currency Forward Contracts and Payable on Open Futures Contracts [Member] | ProShares Ultra Euro [Member] |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Derivative liability not designated as hedging instrument, Unrealized Depreciation | 35 | 19,946
Foreign Exchange Contracts [Member] | Unrealized Depreciation on Foreign Currency Forward Contracts and Payable on Open Futures Contracts [Member] | ProShares Ultra Yen [Member] |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Derivative liability not designated as hedging instrument, Unrealized Depreciation | 42,233 | 163,361
Foreign Exchange Contracts [Member] | Unrealized Appreciation on Foreign Currency Forward Contracts and 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 | 192,985 | 917,605
Foreign Exchange Contracts [Member] | Unrealized Appreciation on Foreign Currency Forward Contracts and 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 | 47,900 | 151,351
Foreign Exchange Contracts [Member] | Unrealized Appreciation on Foreign Currency Forward Contracts and 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 | 6,121,534 | 31,317,568
Foreign Exchange Contracts [Member] | Unrealized Appreciation on Foreign Currency Forward Contracts and 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 | 21,019 | 120,908
Foreign Exchange Contracts [Member] | Unrealized Appreciation on Foreign Currency Forward Contracts and 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 | 1,004 | 4,052
VIX Futures Contracts [Member] | Receivables on Open Futures Contracts and 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 | 8,083,199 | 8,116,955
VIX Futures Contracts [Member] | Payable on Open Futures Contracts and Unrealized Depreciation on Swap Agreements [Member] | ProShares VIX Short-Term Futures ETF [Member] |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Derivative liability not designated as hedging instrument, Unrealized Depreciation | 5,026,965 | 16,652,686
VIX Futures Contracts [Member] | Payable on Open Futures Contracts and Unrealized Depreciation on Swap Agreements [Member] | ProShares VIX Mid-Term Futures ETF [Member] |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Derivative liability not designated as hedging instrument, Unrealized Depreciation | 2,007,210 | 4,896,689
VIX Futures Contracts [Member] | Payable on Open Futures Contracts and Unrealized Depreciation on Swap Agreements [Member] | ProShares Short VIX Short-Term Futures ETF [Member] |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Derivative liability not designated as hedging instrument, Unrealized Depreciation | 29,701,827 |
VIX Futures Contracts [Member] | Payable on Open Futures Contracts and Unrealized Depreciation on Swap Agreements [Member] | ProShares Ultra VIX Short-Term Futures ETF [Member] |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |
Derivative liability not designated as hedging instrument, Unrealized Depreciation |  | $ 24,009,911

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- Definition Derivative asset not designated as hedging instrument, unrealized appreciation. + References No definition available. + Details
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- Definition Derivative liability not designated as hedging instrument, unrealized depreciation. + References No definition available. + Details
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