v2.4.1.9

Schedule of Investments - Futures Contracts Sold (Parenthetical) (Detail) (Futures Contracts Sold [Member], USD $) | 3 Months Ended
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Mar. 31, 2015
ProShares Managed Futures Strategy [Member] |
Schedule of Investments [Line Items] |
Cash collateral pledged to cover margin requirements | $ 269,253 ck0001415311_CashCollateralPledgedToCoverMarginRequirements / us-gaap_DerivativeInstrumentRiskAxis = ck0001415311_FuturesContractsSoldMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesManagedFuturesStrategyMember
ProShares Short VIX Short-Term Futures ETF [Member] |
Schedule of Investments [Line Items] |
Cash collateral pledged to cover margin requirements | 55,500,260 ck0001415311_CashCollateralPledgedToCoverMarginRequirements / us-gaap_DerivativeInstrumentRiskAxis = ck0001415311_FuturesContractsSoldMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesShortVixShortTermFuturesEtfMember
ProShares UltraShort Bloomberg Crude Oil [Member] |
Schedule of Investments [Line Items] |
Cash collateral pledged to cover margin requirements | 20,594,295 ck0001415311_CashCollateralPledgedToCoverMarginRequirements / us-gaap_DerivativeInstrumentRiskAxis = ck0001415311_FuturesContractsSoldMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortBloombergCrudeOilMember
ProShares UltraShort Bloomberg Natural Gas [Member] |
Schedule of Investments [Line Items] |
Cash collateral pledged to cover margin requirements | 1,708,036 ck0001415311_CashCollateralPledgedToCoverMarginRequirements / us-gaap_DerivativeInstrumentRiskAxis = ck0001415311_FuturesContractsSoldMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortBloombergNaturalGasMember
ProShares UltraShort Gold [Member] |
Schedule of Investments [Line Items] |
Cash collateral pledged to cover margin requirements | 8,800 ck0001415311_CashCollateralPledgedToCoverMarginRequirements / us-gaap_DerivativeInstrumentRiskAxis = ck0001415311_FuturesContractsSoldMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortGoldMember
ProShares UltraShort Silver [Member] |
Schedule of Investments [Line Items] |
Cash collateral pledged to cover margin requirements | 16,940 ck0001415311_CashCollateralPledgedToCoverMarginRequirements / us-gaap_DerivativeInstrumentRiskAxis = ck0001415311_FuturesContractsSoldMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortSilverMember
ProShares Short Euro [Member] |
Schedule of Investments [Line Items] |
Cash collateral pledged to cover margin requirements | 511,500 ck0001415311_CashCollateralPledgedToCoverMarginRequirements / us-gaap_DerivativeInstrumentRiskAxis = ck0001415311_FuturesContractsSoldMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesShortEuroMember
ProShares UltraShort Australian Dollar [Member] |
Schedule of Investments [Line Items] |
Cash collateral pledged to cover margin requirements | $ 382,125 ck0001415311_CashCollateralPledgedToCoverMarginRequirements / us-gaap_DerivativeInstrumentRiskAxis = ck0001415311_FuturesContractsSoldMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortAustralianDollarMember

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