v2.4.0.8

Schedule of Investments - Future Contracts Purchased (Parenthetical) (Detail) (USD $)	3 Months Ended
	Mar. 31, 2014
ProShares Ultra DJ-UBS Crude Oil [Member]
Schedule of Investments [Line Items]
Cash Collateral Pledged To Cover Margin Requirements	$ 2,925,780
ProShares Ultra DJ-UBS Natural Gas [Member]
Schedule of Investments [Line Items]
Cash Collateral Pledged To Cover Margin Requirements	3,204,300
ProShares Ultra Gold [Member]
Schedule of Investments [Line Items]
Cash Collateral Pledged To Cover Margin Requirements	15,950
ProShares Ultra Silver [Member]
Schedule of Investments [Line Items]
Cash Collateral Pledged To Cover Margin Requirements	22,000
ProShares Ultra Australian Dollar [Member]
Schedule of Investments [Line Items]
Cash Collateral Pledged To Cover Margin Requirements	152,625
ProShares VIX Short-Term Futures ETF [Member]
Schedule of Investments [Line Items]
Cash Collateral Pledged To Cover Margin Requirements	24,889,000
ProShares VIX Mid-Term Futures ETF [Member]
Schedule of Investments [Line Items]
Cash Collateral Pledged To Cover Margin Requirements	9,129,600
ProShares Ultra VIX Short-Term Futures ETF [Member]
Schedule of Investments [Line Items]
Cash Collateral Pledged To Cover Margin Requirements	$ 134,046,000

X

- Definition

Cash collateral pledged to cover margin requirements.

+ References

No definition available.

+ Details

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Namespace Prefix:	ck0001415311_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

X

- Details

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