v2.4.0.6

Schedule of Investments (Futures Contracts Purchased) (Parenthetical) (Detail) (USD $) | 3 Months Ended
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Mar. 31, 2013
ProShares Ultra DJ-UBS Crude Oil [Member] |
Schedule of Investments [Line Items] |
Cash Collateral Pledged To Cover Margin Requirements | $ 13,909,500
ProShares Ultra DJ-UBS Natural Gas [Member] |
Schedule of Investments [Line Items] |
Cash Collateral Pledged To Cover Margin Requirements | 5,885,880
ProShares Ultra Gold [Member] |
Schedule of Investments [Line Items] |
Cash Collateral Pledged To Cover Margin Requirements | 11,880
ProShares Ultra Silver [Member] |
Schedule of Investments [Line Items] |
Cash Collateral Pledged To Cover Margin Requirements | 20,900
ProShares Ultra Australian Dollar [Member] |
Schedule of Investments [Line Items] |
Cash Collateral Pledged To Cover Margin Requirements | 133,650
ProShares VIX Short-Term Futures ETF [Member] |
Schedule of Investments [Line Items] |
Cash Collateral Pledged To Cover Margin Requirements | 67,081,496
ProShares VIX Mid-Term Futures ETF [Member] |
Schedule of Investments [Line Items] |
Cash Collateral Pledged To Cover Margin Requirements | 16,951,501
ProShares Ultra VIX Short-Term Futures ETF [Member] |
Schedule of Investments [Line Items] |
Cash Collateral Pledged To Cover Margin Requirements | $ 211,090,492

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- Definition Cash collateral pledged to cover margin requirements + References No definition available. + Details
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Balance Type: | debit
Period Type: | duration

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- Details
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Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration