v2.4.0.6

Schedule of Investments (Futures Contracts Sold) (Parenthetical) (Detail) (USD $)	3 Months Ended
	Mar. 31, 2013
ProShares UltraShort DJ-UBS Crude Oil [Member]
Schedule of Investments [Line Items]
Cash Collateral Pledged To Cover Margin Requirements	$ 7,563,600
ProShares UltraShort DJ-UBS Natural Gas [Member]
Schedule of Investments [Line Items]
Cash Collateral Pledged To Cover Margin Requirements	2,887,500
ProShares UltraShort Gold [Member]
Schedule of Investments [Line Items]
Cash Collateral Pledged To Cover Margin Requirements	11,880
ProShares UltraShort Silver [Member]
Schedule of Investments [Line Items]
Cash Collateral Pledged To Cover Margin Requirements	20,900
ProShares Short Euro [Member]
Schedule of Investments [Line Items]
Cash Collateral Pledged To Cover Margin Requirements	59,400
ProShares UltraShort Australian Dollar [Member]
Schedule of Investments [Line Items]
Cash Collateral Pledged To Cover Margin Requirements	117,150
ProShares Short VIX Short-Term Futures ETF [Member]
Schedule of Investments [Line Items]
Cash Collateral Pledged To Cover Margin Requirements	$ 21,073,502

X

- Definition

Cash collateral pledged to cover margin requirements

+ References

No definition available.

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X

- Details

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