v2.4.0.6

Schedule of Investments (Futures Contracts Purchased) (Parenthetical) (Detail) (USD $)	3 Months Ended
	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

X

- Definition

Cash collateral pledged to cover margin requirements

+ References

No definition available.

+ Details

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Period Type:	duration

X

- Details

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