v2.4.1.9

Schedule of Investments - Futures Contracts Purchased (Parenthetical) (Detail) (Futures Contracts Purchased [Member], USD $) | 3 Months Ended
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Mar. 31, 2015
ProShares VIX Short-Term Futures ETF [Member] |
Schedule of Investments [Line Items] |
Cash collateral pledged to cover margin requirements | $ 11,020,165 ck0001415311_CashCollateralPledgedToCoverMarginRequirements / us-gaap_DerivativeInstrumentRiskAxis = ck0001415311_FuturesContractsPurchasedMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesVixShortTermFuturesEtfMember
ProShares VIX Mid-Term Futures ETF [Member] |
Schedule of Investments [Line Items] |
Cash collateral pledged to cover margin requirements | 2,134,050 ck0001415311_CashCollateralPledgedToCoverMarginRequirements / us-gaap_DerivativeInstrumentRiskAxis = ck0001415311_FuturesContractsPurchasedMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesVixMidTermFuturesEtfMember
ProShares Ultra VIX Short-Term Futures ETF [Member] |
Schedule of Investments [Line Items] |
Cash collateral pledged to cover margin requirements | 73,653,370 ck0001415311_CashCollateralPledgedToCoverMarginRequirements / us-gaap_DerivativeInstrumentRiskAxis = ck0001415311_FuturesContractsPurchasedMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraVixShortTermFuturesEtfMember
ProShares Ultra Bloomberg Crude Oil [Member] |
Schedule of Investments [Line Items] |
Cash collateral pledged to cover margin requirements | 13,420,311 ck0001415311_CashCollateralPledgedToCoverMarginRequirements / us-gaap_DerivativeInstrumentRiskAxis = ck0001415311_FuturesContractsPurchasedMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraBloombergCrudeOilMember
ProShares Ultra Bloomberg Natural Gas [Member] |
Schedule of Investments [Line Items] |
Cash collateral pledged to cover margin requirements | 3,842,480 ck0001415311_CashCollateralPledgedToCoverMarginRequirements / us-gaap_DerivativeInstrumentRiskAxis = ck0001415311_FuturesContractsPurchasedMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraBloombergNaturalGasMember
ProShares Ultra Gold [Member] |
Schedule of Investments [Line Items] |
Cash collateral pledged to cover margin requirements | 8,800 ck0001415311_CashCollateralPledgedToCoverMarginRequirements / us-gaap_DerivativeInstrumentRiskAxis = ck0001415311_FuturesContractsPurchasedMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraGoldMember
ProShares Ultra Silver [Member] |
Schedule of Investments [Line Items] |
Cash collateral pledged to cover margin requirements | 16,940 ck0001415311_CashCollateralPledgedToCoverMarginRequirements / us-gaap_DerivativeInstrumentRiskAxis = ck0001415311_FuturesContractsPurchasedMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraSilverMember
ProShares Ultra Australian Dollar [Member] |
Schedule of Investments [Line Items] |
Cash collateral pledged to cover margin requirements | $ 152,460 ck0001415311_CashCollateralPledgedToCoverMarginRequirements / us-gaap_DerivativeInstrumentRiskAxis = ck0001415311_FuturesContractsPurchasedMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraAustralianDollarMember

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