v2.4.0.8

Schedule of Investments - Futures Contracts Sold (Parenthetical) (Detail) (USD $)	3 Months Ended
	Mar. 31, 2014
ProShares Short VIX Short-Term Futures ETF [Member]
Schedule of Investments [Line Items]
Cash Collateral Pledged To Cover Margin Requirements	$ 44,907,500
ProShares UltraShort DJ-UBS Natural Gas [Member]
Schedule of Investments [Line Items]
Cash Collateral Pledged To Cover Margin Requirements	11,104,500
ProShares UltraShort Gold [Member]
Schedule of Investments [Line Items]
Cash Collateral Pledged To Cover Margin Requirements	15,950
ProShares UltraShort Silver [Member]
Schedule of Investments [Line Items]
Cash Collateral Pledged To Cover Margin Requirements	22,000
ProShares Short Euro [Member]
Schedule of Investments [Line Items]
Cash Collateral Pledged To Cover Margin Requirements	101,475
ProShares UltraShort Australian Dollar [Member]
Schedule of Investments [Line Items]
Cash Collateral Pledged To Cover Margin Requirements	934,065
ProShares UltraShort DJ-UBS Crude Oil [Member]
Schedule of Investments [Line Items]
Cash Collateral Pledged To Cover Margin Requirements	$ 9,384,320

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