v2.4.0.8

Schedule of Investments - Futures Contracts Sold (Parenthetical) (Detail) (USD $)	6 Months Ended
	Jun. 30, 2014
ProShares UltraShort Bloomberg Crude Oil [Member]
Schedule of Investments [Line Items]
Cash collateral pledged to cover margin requirements	$ 9,154,200
ProShares UltraShort Bloomberg Natural Gas [Member]
Schedule of Investments [Line Items]
Cash collateral pledged to cover margin requirements	6,400,680
ProShares UltraShort Gold [Member]
Schedule of Investments [Line Items]
Cash collateral pledged to cover margin requirements	13,200
ProShares UltraShort Silver [Member]
Schedule of Investments [Line Items]
Cash collateral pledged to cover margin requirements	18,150
ProShares Short Euro [Member]
Schedule of Investments [Line Items]
Cash collateral pledged to cover margin requirements	182,600
ProShares UltraShort Australian Dollar [Member]
Schedule of Investments [Line Items]
Cash collateral pledged to cover margin requirements	707,850
ProShares Short VIX Short-Term Futures ETF [Member]
Schedule of Investments [Line Items]
Cash collateral pledged to cover margin requirements	$ 38,188,800

X

- Definition

Cash collateral pledged to cover margin requirements.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Details

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