v2.4.0.6

Schedule of Investments (Futures Contracts Sold) (Detail) (USD $) | Mar. 31, 2013
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ProShares UltraShort DJ-UBS Crude Oil [Member] |  |
Schedule of Investments [Line Items] |  |
Unrealized Appreciation (Depreciation) | $ (11,368,414) | [1]
ProShares UltraShort DJ-UBS Crude Oil [Member] | Crude Oil - NYMEX, expires May 2013 [Member] |  |
Schedule of Investments [Line Items] |  |
Number of Contracts | 1,528 | [2]
Notional Amount at Value | 148,567,440 | [2]
Unrealized Appreciation (Depreciation) | 231,524 | [2]
ProShares UltraShort DJ-UBS Natural Gas [Member] | Natural Gas - NYMEX, expires May 2013 [Member] |  |
Schedule of Investments [Line Items] |  |
Number of Contracts | 1,250 | [3]
Notional Amount at Value | 50,300,000 | [3]
Unrealized Appreciation (Depreciation) | (3,496,753) | [3]
ProShares UltraShort Gold [Member] |  |
Schedule of Investments [Line Items] |  |
Unrealized Appreciation (Depreciation) | (3,246,282) | [1]
ProShares UltraShort Gold [Member] | Gold Futures - COMEX, Expires June 2013 [Member] |  |
Schedule of Investments [Line Items] |  |
Number of Contracts | 2 | [4]
Notional Amount at Value | 319,140 | [4]
Unrealized Appreciation (Depreciation) | (1,410) | [4]
ProShares UltraShort Silver [Member] |  |
Schedule of Investments [Line Items] |  |
Unrealized Appreciation (Depreciation) | 255,288 | [1]
ProShares UltraShort Silver [Member] | Silver Futures - COMEX, expires May 2013 [Member] |  |
Schedule of Investments [Line Items] |  |
Number of Contracts | 2 | [5]
Notional Amount at Value | 283,230 | [5]
Unrealized Appreciation (Depreciation) | 27,520 | [5]
ProShares Short Euro [Member] | Euro Fx Currency Futures - CME, expires June 2013 [Member] |  |
Schedule of Investments [Line Items] |  |
Number of Contracts | 24 | [6]
Notional Amount at Value | 3,846,900 | [6]
Unrealized Appreciation (Depreciation) | 61,713 | [6]
ProShares UltraShort Australian Dollar [Member] | Australian Dollar Fx Currency Futures - CME, expires June 2013 [Member] |  |
Schedule of Investments [Line Items] |  |
Number of Contracts | 71 | [7]
Notional Amount at Value | 7,350,630 | [7]
Unrealized Appreciation (Depreciation) | (109,570) | [7]
ProShares Short VIX Short-Term Futures ETF [Member] |  |
Schedule of Investments [Line Items] |  |
Unrealized Appreciation (Depreciation) | 2,388,716 | [8]
ProShares Short VIX Short-Term Futures ETF [Member] | VIX Futures - CBOE, expires April 2013 [Member] |  |
Schedule of Investments [Line Items] |  |
Number of Contracts | 2,965 | [8]
Notional Amount at Value | 42,103,000 | [8]
Unrealized Appreciation (Depreciation) | 2,122,730 | [8]
ProShares Short VIX Short-Term Futures ETF [Member] | VIX Futures - CBOE, expires May 2013 [Member] |  |
Schedule of Investments [Line Items] |  |
Number of Contracts | 1,718 | [8]
Notional Amount at Value | 26,800,800 | [8]
Unrealized Appreciation (Depreciation) | $ 265,986 | [8]
[1] | The positions and counterparties herein are as of March 31, 2013. The Funds continually evaluate different counterparties for their transactions and counterparties are subject to change. New counterparties can be added at any time.
[2] | Cash collateral in the amount of $7,563,600 was pledged to cover margin requirements for open futures contracts as of March 31, 2013.
[3] | Cash collateral in the amount of $2,887,500 was pledged to cover margin requirements for open futures contracts as of March 31, 2013.
[4] | Cash collateral in the amount of $11,880 was pledged to cover margin requirements for open futures contracts as of March 31, 2013.
[5] | Cash collateral in the amount of $20,900 was pledged to cover margin requirements for open futures contracts as of March 31, 2013.
[6] | Cash collateral in the amount of $59,400 was pledged to cover margin requirements for open futures contracts as of March 31, 2013.
[7] | Cash collateral in the amount of $117,150 was pledged to cover margin requirements for open futures contracts as of March 31, 2013.
[8] | Cash collateral in the amount of $21,073,502 was pledged to cover margin requirements for open futures contracts as of March 31, 2013.

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- Definition This element represents the net excess or deficiency of the fair value of an investment (security, contract) over or under its cost (face amount, notional amount), respectively, which excess value or deficiency has not been recognized in earnings of the entity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher AICPA -Name Audit and Accounting Guide (AAG) -Number AAG-INV -Section Glossary -IssueDate 2008-05-01 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. + Details
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