v2.4.1.9
Schedule of Investments - Short-Term U.S. Government and Agency Obligations (Parenthetical) (Detail) (USD $)
3 Months Ended
Mar. 31, 2015
ProShares VIX Short-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Short-term U.S. government and agency obligations percentage of shareholders' equity 88.00%ck0001415311_ShortTermUSGovernmentAndAgencyObligationsOfShareholdersEquity
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesVixShortTermFuturesEtfMember
Total short-term U.S. government and agency obligations, cost $ 131,183,329ck0001415311_ShortTermUSGovernmentAndAgencyObligationsCost
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesVixShortTermFuturesEtfMember
ProShares VIX Mid-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Short-term U.S. government and agency obligations percentage of shareholders' equity 98.00%ck0001415311_ShortTermUSGovernmentAndAgencyObligationsOfShareholdersEquity
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesVixMidTermFuturesEtfMember
Total short-term U.S. government and agency obligations, cost 27,674,827ck0001415311_ShortTermUSGovernmentAndAgencyObligationsCost
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesVixMidTermFuturesEtfMember
ProShares Short VIX Short-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Short-term U.S. government and agency obligations percentage of shareholders' equity 79.00%ck0001415311_ShortTermUSGovernmentAndAgencyObligationsOfShareholdersEquity
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesShortVixShortTermFuturesEtfMember
Total short-term U.S. government and agency obligations, cost 222,916,842ck0001415311_ShortTermUSGovernmentAndAgencyObligationsCost
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesShortVixShortTermFuturesEtfMember
ProShares Ultra VIX Short-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Short-term U.S. government and agency obligations percentage of shareholders' equity 82.00%ck0001415311_ShortTermUSGovernmentAndAgencyObligationsOfShareholdersEquity
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraVixShortTermFuturesEtfMember
Total short-term U.S. government and agency obligations, cost 569,902,127ck0001415311_ShortTermUSGovernmentAndAgencyObligationsCost
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraVixShortTermFuturesEtfMember
ProShares UltraShort Bloomberg Commodity [Member]  
Schedule of Investments [Line Items]  
Short-term U.S. government and agency obligations percentage of shareholders' equity 86.00%ck0001415311_ShortTermUSGovernmentAndAgencyObligationsOfShareholdersEquity
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortBloombergCommodityMember
Total short-term U.S. government and agency obligations, cost 4,990,615ck0001415311_ShortTermUSGovernmentAndAgencyObligationsCost
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortBloombergCommodityMember
ProShares UltraShort Bloomberg Crude Oil [Member]  
Schedule of Investments [Line Items]  
Short-term U.S. government and agency obligations percentage of shareholders' equity 86.00%ck0001415311_ShortTermUSGovernmentAndAgencyObligationsOfShareholdersEquity
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortBloombergCrudeOilMember
Total short-term U.S. government and agency obligations, cost 319,738,023ck0001415311_ShortTermUSGovernmentAndAgencyObligationsCost
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortBloombergCrudeOilMember
ProShares UltraShort Bloomberg Natural Gas [Member]  
Schedule of Investments [Line Items]  
Short-term U.S. government and agency obligations percentage of shareholders' equity 82.00%ck0001415311_ShortTermUSGovernmentAndAgencyObligationsOfShareholdersEquity
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortBloombergNaturalGasMember
Total short-term U.S. government and agency obligations, cost 8,979,490ck0001415311_ShortTermUSGovernmentAndAgencyObligationsCost
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortBloombergNaturalGasMember
ProShares UltraShort Gold [Member]  
Schedule of Investments [Line Items]  
Short-term U.S. government and agency obligations percentage of shareholders' equity 102.00%ck0001415311_ShortTermUSGovernmentAndAgencyObligationsOfShareholdersEquity
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortGoldMember
Total short-term U.S. government and agency obligations, cost 79,438,253ck0001415311_ShortTermUSGovernmentAndAgencyObligationsCost
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortGoldMember
ProShares UltraShort Silver [Member]  
Schedule of Investments [Line Items]  
Short-term U.S. government and agency obligations percentage of shareholders' equity 88.00%ck0001415311_ShortTermUsGovernmentAndAgencyObligationsAsPercentageOfShareholdersEquity
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortSilverMember
Total short-term U.S. government and agency obligations, cost 50,000,423ck0001415311_ShortTermUSGovernmentAndAgencyObligationsCost
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortSilverMember
ProShares Short Euro [Member]  
Schedule of Investments [Line Items]  
Short-term U.S. government and agency obligations percentage of shareholders' equity 89.00%ck0001415311_ShortTermUsGovernmentAndAgencyObligationsAsPercentageOfShareholdersEquity
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesShortEuroMember
Total short-term U.S. government and agency obligations, cost 18,011,817ck0001415311_ShortTermUSGovernmentAndAgencyObligationsCost
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesShortEuroMember
ProShares UltraShort Australian Dollar [Member]  
Schedule of Investments [Line Items]  
Short-term U.S. government and agency obligations percentage of shareholders' equity 84.00%ck0001415311_ShortTermUsGovernmentAndAgencyObligationsAsPercentageOfShareholdersEquity
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortAustralianDollarMember
Total short-term U.S. government and agency obligations, cost 16,932,386ck0001415311_ShortTermUSGovernmentAndAgencyObligationsCost
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortAustralianDollarMember
ProShares UltraShort Euro [Member]  
Schedule of Investments [Line Items]  
Short-term U.S. government and agency obligations percentage of shareholders' equity 89.00%ck0001415311_ShortTermUsGovernmentAndAgencyObligationsAsPercentageOfShareholdersEquity
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortEuroMember
Total short-term U.S. government and agency obligations, cost 549,433,835ck0001415311_ShortTermUSGovernmentAndAgencyObligationsCost
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortEuroMember
ProShares UltraShort Yen [Member]  
Schedule of Investments [Line Items]  
Short-term U.S. government and agency obligations percentage of shareholders' equity 101.00%ck0001415311_ShortTermUSGovernmentAndAgencyObligationsOfShareholdersEquity
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortYenMember
Total short-term U.S. government and agency obligations, cost 444,086,152ck0001415311_ShortTermUSGovernmentAndAgencyObligationsCost
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortYenMember
ProShares Ultra Bloomberg Commodity [Member]  
Schedule of Investments [Line Items]  
Short-term U.S. government and agency obligations percentage of shareholders' equity 98.00%ck0001415311_ShortTermUSGovernmentAndAgencyObligationsOfShareholdersEquity
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraBloombergCommodityMember
Total short-term U.S. government and agency obligations, cost 2,242,745ck0001415311_ShortTermUSGovernmentAndAgencyObligationsCost
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraBloombergCommodityMember
ProShares Ultra Bloomberg Crude Oil [Member]  
Schedule of Investments [Line Items]  
Short-term U.S. government and agency obligations percentage of shareholders' equity 106.00%ck0001415311_ShortTermUSGovernmentAndAgencyObligationsOfShareholdersEquity
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraBloombergCrudeOilMember
Total short-term U.S. government and agency obligations, cost 1,066,107,943ck0001415311_ShortTermUSGovernmentAndAgencyObligationsCost
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraBloombergCrudeOilMember
ProShares Ultra Bloomberg Natural Gas [Member]  
Schedule of Investments [Line Items]  
Short-term U.S. government and agency obligations percentage of shareholders' equity 93.00%ck0001415311_ShortTermUSGovernmentAndAgencyObligationsOfShareholdersEquity
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraBloombergNaturalGasMember
Total short-term U.S. government and agency obligations, cost 57,169,151ck0001415311_ShortTermUSGovernmentAndAgencyObligationsCost
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraBloombergNaturalGasMember
ProShares Ultra Gold [Member]  
Schedule of Investments [Line Items]  
Short-term U.S. government and agency obligations percentage of shareholders' equity 98.00%ck0001415311_ShortTermUSGovernmentAndAgencyObligationsOfShareholdersEquity
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraGoldMember
Total short-term U.S. government and agency obligations, cost 94,231,992ck0001415311_ShortTermUSGovernmentAndAgencyObligationsCost
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraGoldMember
ProShares Ultra Silver [Member]  
Schedule of Investments [Line Items]  
Short-term U.S. government and agency obligations percentage of shareholders' equity 93.00%ck0001415311_ShortTermUSGovernmentAndAgencyObligationsOfShareholdersEquity
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraSilverMember
Total short-term U.S. government and agency obligations, cost 294,492,151ck0001415311_ShortTermUSGovernmentAndAgencyObligationsCost
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraSilverMember
ProShares Ultra Australian Dollar [Member]  
Schedule of Investments [Line Items]  
Short-term U.S. government and agency obligations percentage of shareholders' equity 92.00%ck0001415311_ShortTermUSGovernmentAndAgencyObligationsOfShareholdersEquity
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraAustralianDollarMember
Total short-term U.S. government and agency obligations, cost 2,201,929ck0001415311_ShortTermUSGovernmentAndAgencyObligationsCost
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraAustralianDollarMember
ProShares Ultra Euro [Member]  
Schedule of Investments [Line Items]  
Short-term U.S. government and agency obligations percentage of shareholders' equity 103.00%ck0001415311_ShortTermUSGovernmentAndAgencyObligationsOfShareholdersEquity
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraEuroMember
Total short-term U.S. government and agency obligations, cost 15,242,859ck0001415311_ShortTermUSGovernmentAndAgencyObligationsCost
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraEuroMember
ProShares Ultra Yen [Member]  
Schedule of Investments [Line Items]  
Short-term U.S. government and agency obligations percentage of shareholders' equity 93.00%ck0001415311_ShortTermUSGovernmentAndAgencyObligationsOfShareholdersEquity
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraYenMember
Total short-term U.S. government and agency obligations, cost $ 5,210,360ck0001415311_ShortTermUSGovernmentAndAgencyObligationsCost
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraYenMember
U.S. Treasury Bills 0.036% Due 04/16/15 [Member] | ProShares VIX Short-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.036%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroThreeSixPercentageDueAprilSixteenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesVixShortTermFuturesEtfMember
Debt instrument, maturity date Apr. 16, 2015
U.S. Treasury Bills 0.036% Due 04/16/15 [Member] | ProShares Ultra VIX Short-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.036%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroThreeSixPercentageDueAprilSixteenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraVixShortTermFuturesEtfMember
Debt instrument, maturity date Apr. 16, 2015
U.S. Treasury Bills 0.036% Due 04/16/15 [Member] | ProShares Ultra Euro [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.036%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroThreeSixPercentageDueAprilSixteenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraEuroMember
Debt instrument, maturity date Apr. 16, 2015
U.S. Treasury Bills 0.026% Due 04/30/15 [Member] | ProShares VIX Short-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.026%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroTwoSixPercentageDueAprilThirtyTwoThousandFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesVixShortTermFuturesEtfMember
Debt instrument, maturity date Apr. 30, 2015
U.S. Treasury Bills 0.026% Due 04/30/15 [Member] | ProShares UltraShort Bloomberg Crude Oil [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.026%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroTwoSixPercentageDueAprilThirtyTwoThousandFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortBloombergCrudeOilMember
Debt instrument, maturity date Apr. 30, 2015
U.S. Treasury Bills 0.061% Due 05/14/15 [Member] | ProShares VIX Short-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.061%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroSixOnePercentageDueMayFourteenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesVixShortTermFuturesEtfMember
Debt instrument, maturity date May 14, 2015
U.S. Treasury Bills 0.061% Due 05/14/15 [Member] | ProShares Ultra VIX Short-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.061%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroSixOnePercentageDueMayFourteenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraVixShortTermFuturesEtfMember
Debt instrument, maturity date May 14, 2015
U.S. Treasury Bills 0.061% Due 05/14/15 [Member] | ProShares UltraShort Bloomberg Natural Gas [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.061%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroSixOnePercentageDueMayFourteenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortBloombergNaturalGasMember
Debt instrument, maturity date May 14, 2015
U.S. Treasury Bills 0.061% Due 05/14/15 [Member] | ProShares Ultra Bloomberg Crude Oil [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.061%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroSixOnePercentageDueMayFourteenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraBloombergCrudeOilMember
Debt instrument, maturity date May 14, 2015
U.S. Treasury Bills 0.017% Due 05/21/15 [Member] | ProShares VIX Short-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.017%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroOneSevenPercentageDueMayTwentyOneTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesVixShortTermFuturesEtfMember
Debt instrument, maturity date May 21, 2015
U.S. Treasury Bills 0.049% Due 05/28/15 [Member] | ProShares VIX Short-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.049%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFourNinePercentageDueMayTwentyEighthTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesVixShortTermFuturesEtfMember
Debt instrument, maturity date May 28, 2015
U.S. Treasury Bills 0.046% Due 06/04/15 [Member] | ProShares VIX Short-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.046%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFourSixPercentageDueJuneFourTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesVixShortTermFuturesEtfMember
Debt instrument, maturity date Jun. 04, 2015
U.S. Treasury Bills 0.046% Due 06/04/15 [Member] | ProShares Ultra VIX Short-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.046%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFourSixPercentageDueJuneFourTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraVixShortTermFuturesEtfMember
Debt instrument, maturity date Jun. 04, 2015
U.S. Treasury Bills 0.046% Due 06/04/15 [Member] | ProShares Ultra Bloomberg Natural Gas [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.046%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFourSixPercentageDueJuneFourTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraBloombergNaturalGasMember
Debt instrument, maturity date Jun. 04, 2015
U.S. Treasury Bills 0.013% Due 06/11/15 [Member] | ProShares VIX Short-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.013%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroOneThreePercentageDueJuneElevenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesVixShortTermFuturesEtfMember
Debt instrument, maturity date Jun. 11, 2015
U.S. Treasury Bills 0.016% Due 06/18/15 [Member] | ProShares VIX Short-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.016%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroOneSixPercentageDueJuneEighteenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesVixShortTermFuturesEtfMember
Debt instrument, maturity date Jun. 18, 2015
U.S. Treasury Bills 0.016% Due 06/18/15 [Member] | ProShares UltraShort Bloomberg Commodity [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.016%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroOneSixPercentageDueJuneEighteenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortBloombergCommodityMember
Debt instrument, maturity date Jun. 18, 2015
U.S. Treasury Bills 0.016% Due 06/18/15 [Member] | ProShares UltraShort Bloomberg Natural Gas [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.016%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroOneSixPercentageDueJuneEighteenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortBloombergNaturalGasMember
Debt instrument, maturity date Jun. 18, 2015
U.S. Treasury Bills 0.016% Due 06/18/15 [Member] | ProShares Ultra Euro [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.016%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroOneSixPercentageDueJuneEighteenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraEuroMember
Debt instrument, maturity date Jun. 18, 2015
U.S. Treasury Bills 0.021% Due 06/25/15 [Member] | ProShares VIX Short-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.021%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroTwoOnePercentageDueJuneTwentyFiveTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesVixShortTermFuturesEtfMember
[1]
Debt instrument, maturity date Jun. 25, 2015 [1]
U.S. Treasury Bills 0.021% Due 06/25/15 [Member] | ProShares Ultra VIX Short-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.021%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroTwoOnePercentageDueJuneTwentyFiveTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraVixShortTermFuturesEtfMember
Debt instrument, maturity date Jun. 25, 2015
U.S. Treasury Bills 0.024% Due 07/02/15 [Member] | ProShares VIX Short-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.024%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroTwoFourPercentageDueJulyTwoTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesVixShortTermFuturesEtfMember
Debt instrument, maturity date Jul. 02, 2015
U.S. Treasury Bills 0.039% Due 07/09/15 [Member] | ProShares VIX Short-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.039%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroThreeNinePercentageDueJulyNineTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesVixShortTermFuturesEtfMember
Debt instrument, maturity date Jul. 09, 2015
U.S. Treasury Bills 0.036% Due 07/16/15 [Member] | ProShares VIX Short-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.036%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroThreeSixPercentageDueJulySixteenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesVixShortTermFuturesEtfMember
Debt instrument, maturity date Jul. 16, 2015
U.S. Treasury Bills 0.036% Due 07/16/15 [Member] | ProShares VIX Mid-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.036%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroThreeSixPercentageDueJulySixteenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesVixMidTermFuturesEtfMember
Debt instrument, maturity date Jul. 16, 2015
U.S. Treasury Bills 0.036% Due 07/16/15 [Member] | ProShares Ultra Bloomberg Commodity [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.036%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroThreeSixPercentageDueJulySixteenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraBloombergCommodityMember
Debt instrument, maturity date Jul. 16, 2015
U.S. Treasury Bills 0.036% Due 07/16/15 [Member] | ProShares Ultra Bloomberg Crude Oil [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.036%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroThreeSixPercentageDueJulySixteenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraBloombergCrudeOilMember
[2]
Debt instrument, maturity date Jul. 16, 2015 [2]
U.S. Treasury Bills 0.036% Due 07/16/15 [Member] | ProShares Ultra Euro [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.036%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroThreeSixPercentageDueJulySixteenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraEuroMember
Debt instrument, maturity date Jul. 16, 2015
U.S. Treasury Bills 0.043% Due 07/23/15 [Member] | ProShares VIX Short-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.043%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFourThreePercentageDueJulyTwentyThreeTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesVixShortTermFuturesEtfMember
Debt instrument, maturity date Jul. 23, 2015
U.S. Treasury Bills 0.035% Due 07/30/15 [Member] | ProShares VIX Short-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.035%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroThreeFivePercentageDueJulyThirtyTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesVixShortTermFuturesEtfMember
Debt instrument, maturity date Jul. 30, 2015
U.S. Treasury Bills 0.035% Due 07/30/15 [Member] | ProShares UltraShort Gold [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.035%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroThreeFivePercentageDueJulyThirtyTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortGoldMember
Debt instrument, maturity date Jul. 30, 2015
U.S. Treasury Bills 0.057% Due 08/06/2015 [Member] | ProShares VIX Short-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.057%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFiveSevenPercentageDueAugustSixTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesVixShortTermFuturesEtfMember
[1]
Debt instrument, maturity date Aug. 06, 2015 [1]
U.S. Treasury Bills 0.050% Due 08/13/15 [Member] | ProShares VIX Short-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.05%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFiveZeroPercentageDueAugustThirteenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesVixShortTermFuturesEtfMember
[1]
Debt instrument, maturity date Aug. 13, 2015 [1]
U.S. Treasury Bills 0.043% Due 04/16/15 [Member] | ProShares VIX Mid-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.043%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFourThreePercentageDueAprilSixteenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesVixMidTermFuturesEtfMember
Debt instrument, maturity date Apr. 16, 2015
U.S. Treasury Bills 0.043% Due 04/16/15 [Member] | ProShares Short VIX Short-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.043%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFourThreePercentageDueAprilSixteenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesShortVixShortTermFuturesEtfMember
Debt instrument, maturity date Apr. 16, 2015
U.S. Treasury Bills 0.043% Due 04/16/15 [Member] | ProShares UltraShort Australian Dollar [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.043%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFourThreePercentageDueAprilSixteenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortAustralianDollarMember
Debt instrument, maturity date Apr. 16, 2015
U.S. Treasury Bills 0.036% Due 04/30/2015 [Member] | ProShares VIX Mid-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.036%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroThreeSixPercentageDueAprilThirtyTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesVixMidTermFuturesEtfMember
Debt instrument, maturity date Apr. 30, 2015
U.S. Treasury Bills 0.031% Due 05/21/15 [Member] | ProShares VIX Mid-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.031%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroThreeOnePercentageDueAprilTwentyOneTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesVixMidTermFuturesEtfMember
Debt instrument, maturity date May 21, 2015
U.S. Treasury Bills 0.071% Due 05/28/15 [Member] | ProShares VIX Mid-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.071%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroSevenOnePercentageDueMayTwentyEightTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesVixMidTermFuturesEtfMember
Debt instrument, maturity date May 28, 2015
U.S. Treasury Bills 0.087% Due 06/11/15 [Member] | ProShares VIX Mid-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.087%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroEightSevenPercentageDueJuneElevenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesVixMidTermFuturesEtfMember
Debt instrument, maturity date Jun. 11, 2015
U.S. Treasury Bills 0.087% Due 06/11/15 [Member] | ProShares UltraShort Bloomberg Commodity [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.087%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroEightSevenPercentageDueJuneElevenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortBloombergCommodityMember
[3]
Debt instrument, maturity date Jun. 11, 2015 [3]
U.S. Treasury Bills 0.015% Due 06/18/15 [Member] | ProShares VIX Mid-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.015%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroOneFivePercentageDueJuneEighteenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesVixMidTermFuturesEtfMember
Debt instrument, maturity date Jun. 18, 2015
U.S. Treasury Bills 0.015% Due 06/18/15 [Member] | ProShares Short VIX Short-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.015%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroOneFivePercentageDueJuneEighteenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesShortVixShortTermFuturesEtfMember
Debt instrument, maturity date Jun. 18, 2015
U.S. Treasury Bills 0.030% Due 07/02/15 [Member] | ProShares VIX Mid-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.03%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroThreeZeroPercentageDueJulySevenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesVixMidTermFuturesEtfMember
Debt instrument, maturity date Jul. 02, 2015
U.S. Treasury Bills 0.030% Due 07/02/15 [Member] | ProShares UltraShort Gold [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.03%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroThreeZeroPercentageDueJulySevenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortGoldMember
[4]
Debt instrument, maturity date Jul. 02, 2015 [4]
U.S. Treasury Bills 0.030% Due 07/02/15 [Member] | ProShares UltraShort Silver [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.03%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroThreeZeroPercentageDueJulySevenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortSilverMember
[4]
Debt instrument, maturity date Jul. 02, 2015 [4]
U.S. Treasury Bills 0.045% Due 08/06/15 [Member] | ProShares VIX Mid-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.045%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFourFivePercentageDueAugustSixTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesVixMidTermFuturesEtfMember
[1]
Debt instrument, maturity date Aug. 06, 2015 [1]
U.S. Treasury Bills 0.045% Due 08/06/15 [Member] | ProShares UltraShort Gold [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.045%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFourFivePercentageDueAugustSixTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortGoldMember
Debt instrument, maturity date Aug. 06, 2015
U.S. Treasury Bills 0.045% Due 08/06/15 [Member] | ProShares Ultra Bloomberg Natural Gas [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.045%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFourFivePercentageDueAugustSixTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraBloombergNaturalGasMember
[1]
Debt instrument, maturity date Aug. 06, 2015 [1]
U.S. Treasury Bills 0.044% Due 05/14/15 [Member] | ProShares Short VIX Short-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.044%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFourFourPercentageDueMayFourteenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesShortVixShortTermFuturesEtfMember
Debt instrument, maturity date May 14, 2015
U.S. Treasury Bills 0.032% Due 05/21/15 [Member] | ProShares Short VIX Short-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.032%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroThreeTwoPercentageDueMayTwentyOneTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesShortVixShortTermFuturesEtfMember
Debt instrument, maturity date May 21, 2015
U.S. Treasury Bills 0.073% Due 05/28/15 [Member] | ProShares Short VIX Short-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.073%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroSevenThreePercentageDueMayTwentyEighthTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesShortVixShortTermFuturesEtfMember
Debt instrument, maturity date May 28, 2015
U.S. Treasury Bills 0.061% Due 06/04/15 [Member] | ProShares Short VIX Short-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.061%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroSixOnePercentageDueJuneFourTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesShortVixShortTermFuturesEtfMember
Debt instrument, maturity date Jun. 04, 2015
U.S. Treasury Bills 0.017% Due 06/11/15 [Member] | ProShares Short VIX Short-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.017%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroOneSevenPercentageDueJuneElevenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesShortVixShortTermFuturesEtfMember
Debt instrument, maturity date Jun. 11, 2015
U.S. Treasury Bills 0.041% Due 06/25/15 [Member] | ProShares Short VIX Short-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.041%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFourOnePercentageDueJuneTwentyFiveTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesShortVixShortTermFuturesEtfMember
[1]
Debt instrument, maturity date Jun. 25, 2015 [1]
U.S. Treasury Bills 0.022% Due 07/02/15 [Member] | ProShares Short VIX Short-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.022%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroTwoTwoPercentageDueJulyTwoTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesShortVixShortTermFuturesEtfMember
[1]
Debt instrument, maturity date Jul. 02, 2015 [1]
U.S. Treasury Bills 0.057% Due 07/19/15 [Member] | ProShares Short VIX Short-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.057%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFiveSevenPercentageDueJulyNineTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesShortVixShortTermFuturesEtfMember
[1]
Debt instrument, maturity date Jul. 09, 2015 [1]
U.S. Treasury Bills 0.028% Due 07/16/15 [Member] | ProShares Short VIX Short-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.028%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroTwoEightPercentageDueJulySixteenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesShortVixShortTermFuturesEtfMember
Debt instrument, maturity date Jul. 16, 2015
U.S. Treasury Bills 0.028% Due 07/16/15 [Member] | ProShares Ultra Bloomberg Natural Gas [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.028%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroTwoEightPercentageDueJulySixteenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraBloombergNaturalGasMember
[1]
Debt instrument, maturity date Jul. 16, 2015 [1]
U.S. Treasury Bills 0.047% Due 07/23/15 [Member] | ProShares Short VIX Short-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.047%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFourSevenPercentageDueJulyTwentyThreeTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesShortVixShortTermFuturesEtfMember
Debt instrument, maturity date Jul. 23, 2015
U.S. Treasury Bills 0.047% Due 07/23/15 [Member] | ProShares Ultra Bloomberg Natural Gas [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.047%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFourSevenPercentageDueJulyTwentyThreeTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraBloombergNaturalGasMember
[1]
Debt instrument, maturity date Jul. 23, 2015 [1]
U.S. Treasury Bills 0.030% Due 07/30/15 [Member] | ProShares Short VIX Short-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.03%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroThreeZeroPercentageDueJulyThirtyTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesShortVixShortTermFuturesEtfMember
Debt instrument, maturity date Jul. 30, 2015
U.S. Treasury Bills 0.030% Due 07/30/15 [Member] | ProShares UltraShort Euro [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.03%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroThreeZeroPercentageDueJulyThirtyTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortEuroMember
Debt instrument, maturity date Jul. 30, 2015
U.S. Treasury Bills 0.061% Due 08/06/15 [Member] | ProShares Short VIX Short-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.061%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroSixOnePercentageDueAugustSixTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesShortVixShortTermFuturesEtfMember
[1]
Debt instrument, maturity date Aug. 06, 2015 [1]
U.S. Treasury Bills 0.045% Due 08/13/15 [Member] | ProShares Short VIX Short-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.045%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFourFivePercentageDueAugustThirteenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesShortVixShortTermFuturesEtfMember
[1]
Debt instrument, maturity date Aug. 13, 2015 [1]
U.S. Treasury Bills 0.045% Due 08/13/15 [Member] | ProShares UltraShort Bloomberg Natural Gas [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.045%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFourFivePercentageDueAugustThirteenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortBloombergNaturalGasMember
[1]
Debt instrument, maturity date Aug. 13, 2015 [1]
U.S. Treasury Bills 0.045% Due 08/13/15 [Member] | ProShares Short Euro [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.045%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFourFivePercentageDueAugustThirteenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesShortEuroMember
Debt instrument, maturity date Aug. 13, 2015
U.S. Treasury Bills 0.045% Due 08/13/15 [Member] | ProShares UltraShort Yen [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.045%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFourFivePercentageDueAugustThirteenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortYenMember
[5]
Debt instrument, maturity date Aug. 13, 2015 [5]
U.S. Treasury Bills 0.001% Due 04/30/15 [Member] | ProShares Ultra VIX Short-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.001%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroZeroOnePercentageDueAprilThirtyTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraVixShortTermFuturesEtfMember
Debt instrument, maturity date Apr. 30, 2015
U.S. Treasury Bills 0.012% Due 05/21/15 [Member] | ProShares Ultra VIX Short-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.012%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroOneTwoPercentageDueMayTwentyOneTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraVixShortTermFuturesEtfMember
Debt instrument, maturity date May 21, 2015
U.S. Treasury Bills 0.012% Due 05/21/15 [Member] | ProShares UltraShort Australian Dollar [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.012%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroOneTwoPercentageDueMayTwentyOneTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortAustralianDollarMember
Debt instrument, maturity date May 21, 2015
U.S. Treasury Bills 0.018% Due 05/28/15 [Member] | ProShares Ultra VIX Short-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.018%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroOneEightPercentageDueMayTwentyEightTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraVixShortTermFuturesEtfMember
Debt instrument, maturity date May 28, 2015
U.S. Treasury Bills 0.010% Due 06/11/15 [Member] | ProShares Ultra VIX Short-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.01%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroOneZeroPercentageDueJuneElevenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraVixShortTermFuturesEtfMember
Debt instrument, maturity date Jun. 11, 2015
U.S. Treasury Bills 0.013% Due 06/18/15 [Member] | ProShares Ultra VIX Short-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.013%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroOneThreePercentageDueJuneEighteenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraVixShortTermFuturesEtfMember
Debt instrument, maturity date Jun. 18, 2015
U.S. Treasury Bills 0.015% Due 07/02/15 [Member] | ProShares Ultra VIX Short-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.015%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroOneFivePercentageDueJulyTwoTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraVixShortTermFuturesEtfMember
[1]
Debt instrument, maturity date Jul. 02, 2015 [1]
U.S. Treasury Bills 0.015% Due 07/02/15 [Member] | ProShares UltraShort Bloomberg Natural Gas [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.015%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroOneFivePercentageDueJulyTwoTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortBloombergNaturalGasMember
[1]
Debt instrument, maturity date Jul. 02, 2015 [1]
U.S. Treasury Bills 0.040% Due 07/09/15 [Member] | ProShares Ultra VIX Short-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.04%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFourZeroPercentageDueJulyNineTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraVixShortTermFuturesEtfMember
[1]
Debt instrument, maturity date Jul. 09, 2015 [1]
U.S. Treasury Bills 0.027% Due 07/16/15 [Member] | ProShares Ultra VIX Short-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.027%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroTwoSevenPercentageDueJulySixteenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraVixShortTermFuturesEtfMember
[1]
Debt instrument, maturity date Jul. 16, 2015 [1]
U.S. Treasury Bills 0.037% Due 07/23/15 [Member] | ProShares Ultra VIX Short-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.037%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroThreeSevenPercentageDueJulyTwentyThreeTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraVixShortTermFuturesEtfMember
Debt instrument, maturity date Jul. 23, 2015
U.S. Treasury Bills 0.037% Due 07/23/15 [Member] | ProShares UltraShort Silver [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.037%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroThreeSevenPercentageDueJulyTwentyThreeTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortSilverMember
[4]
Debt instrument, maturity date Jul. 23, 2015 [4]
U.S. Treasury Bills 0.031% Due 07/30/15 [Member] | ProShares Ultra VIX Short-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.031%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroThreeOnePercentageDueJulyThirtyTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraVixShortTermFuturesEtfMember
[1]
Debt instrument, maturity date Jul. 30, 2015 [1]
U.S. Treasury Bills 0.046% Due 08/06/15 [Member] | ProShares Ultra VIX Short-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.046%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFourSixPercentageDueAugustSixTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraVixShortTermFuturesEtfMember
[1]
Debt instrument, maturity date Aug. 06, 2015 [1]
U.S. Treasury Bills 0.048% Due 08/13/15 [Member] | ProShares Ultra VIX Short-Term Futures ETF [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.048%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFourEightPercentageDueAugustThirteenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraVixShortTermFuturesEtfMember
[1]
Debt instrument, maturity date Aug. 13, 2015 [1]
U.S. Treasury Bills 0.048% Due 08/13/15 [Member] | ProShares Ultra Bloomberg Crude Oil [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.048%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFourEightPercentageDueAugustThirteenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraBloombergCrudeOilMember
[2]
Debt instrument, maturity date Aug. 13, 2015 [2]
U.S. Treasury Bills 0.039% Due 04/16/15 [Member] | ProShares UltraShort Bloomberg Commodity [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.039%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroThreeNinePercentageDueAprilSixteenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortBloombergCommodityMember
[3]
Debt instrument, maturity date Apr. 16, 2015 [3]
U.S. Treasury Bills 0.050% Due 07/09/15 [Member] | ProShares UltraShort Bloomberg Commodity [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.05%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFiveZeroPercentageDueJulyNineTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortBloombergCommodityMember
[3]
Debt instrument, maturity date Jul. 09, 2015 [3]
U.S. Treasury Bills 0.050% Due 07/09/15 [Member] | ProShares Short Euro [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.05%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFiveZeroPercentageDueJulyNineTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesShortEuroMember
Debt instrument, maturity date Jul. 09, 2015
U.S. Treasury Bills 0.050% Due 07/09/15 [Member] | ProShares UltraShort Euro [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.05%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFiveZeroPercentageDueJulyNineTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortEuroMember
[5]
Debt instrument, maturity date Jul. 09, 2015 [5]
U.S. Treasury Bills 0.038% Due 07/23/15 [Member] | ProShares UltraShort Bloomberg Commodity [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.038%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroThreeEightPercentageDueJulyTwentyThreeTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortBloombergCommodityMember
[3]
Debt instrument, maturity date Jul. 23, 2015 [3]
U.S. Treasury Bills 0.038% Due 07/23/15 [Member] | ProShares UltraShort Gold [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.038%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroThreeEightPercentageDueJulyTwentyThreeTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortGoldMember
[4]
Debt instrument, maturity date Jul. 23, 2015 [4]
U.S. Treasury Bills 0.038% Due 07/23/15 [Member] | ProShares Short Euro [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.038%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroThreeEightPercentageDueJulyTwentyThreeTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesShortEuroMember
Debt instrument, maturity date Jul. 23, 2015
U.S. Treasury Bills 0.038% Due 07/23/15 [Member] | ProShares UltraShort Australian Dollar [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.038%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroThreeEightPercentageDueJulyTwentyThreeTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortAustralianDollarMember
Debt instrument, maturity date Jul. 23, 2015
U.S. Treasury Bills 0.041% Due 04/16/15 [Member] | ProShares UltraShort Bloomberg Crude Oil [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.041%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFourOnePercentageDueAprilSixteenTwoThousandFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortBloombergCrudeOilMember
Debt instrument, maturity date Apr. 16, 2015
U.S. Treasury Bills 0.041% Due 04/16/15 [Member] | ProShares UltraShort Gold [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.041%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFourOnePercentageDueAprilSixteenTwoThousandFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortGoldMember
Debt instrument, maturity date Apr. 06, 2015
U.S. Treasury Bills 0.041% Due 04/16/15 [Member] | ProShares Short Euro [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.041%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFourOnePercentageDueAprilSixteenTwoThousandFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesShortEuroMember
Debt instrument, maturity date Apr. 16, 2015
U.S. Treasury Bills 0.041% Due 04/16/15 [Member] | ProShares UltraShort Euro [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.041%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFourOnePercentageDueAprilSixteenTwoThousandFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortEuroMember
[5]
Debt instrument, maturity date Apr. 16, 2015 [5]
U.S. Treasury Bills 0.041% Due 04/16/15 [Member] | ProShares UltraShort Yen [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.041%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFourOnePercentageDueAprilSixteenTwoThousandFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortYenMember
Debt instrument, maturity date Apr. 16, 2015
U.S. Treasury Bills 0.041% Due 04/16/15 [Member] | ProShares Ultra Silver [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.041%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFourOnePercentageDueAprilSixteenTwoThousandFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraSilverMember
[4]
Debt instrument, maturity date Apr. 16, 2015 [4]
U.S. Treasury Bills 0.064% Due 05/14/15 [Member] | ProShares UltraShort Bloomberg Crude Oil [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.064%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroSixFourPercentageDueMayFourteenTwoThousandFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortBloombergCrudeOilMember
[2]
Debt instrument, maturity date May 14, 2015 [2]
U.S. Treasury Bills 0.064% Due 05/14/15 [Member] | ProShares Ultra Silver [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.064%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroSixFourPercentageDueMayFourteenTwoThousandFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraSilverMember
[4]
Debt instrument, maturity date May 14, 2015 [4]
U.S. Treasury Bills 0.023% Due 05/21/15 [Member] | ProShares UltraShort Bloomberg Crude Oil [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.023%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroTwoThreePercentageDueMayTwentyOneTwoThousandFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortBloombergCrudeOilMember
[2]
Debt instrument, maturity date May 21, 2015 [2]
U.S. Treasury Bills 0.020% Due 05/28/15 [Member] | ProShares UltraShort Bloomberg Crude Oil [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.02%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroTwoZeroPercentageDueMayTwentyEightTwoThousandFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortBloombergCrudeOilMember
Debt instrument, maturity date May 28, 2015
U.S. Treasury Bills 0.069% Due 06/04/15 [Member] | ProShares UltraShort Bloomberg Crude Oil [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.069%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroSixNinePercentageDueJuneFourTwoThousandFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortBloombergCrudeOilMember
Debt instrument, maturity date Jun. 04, 2015
U.S. Treasury Bills 0.013% Due 06/11/15 [Member] | ProShares UltraShort Bloomberg Crude Oil [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.013%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroOneThreePercentageDueJuneElevenTwoThousandFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortBloombergCrudeOilMember
[2]
Debt instrument, maturity date Jun. 11, 2015 [2]
U.S. Treasury Bills 0.002% Due 06/18/15 [Member] | ProShares UltraShort Bloomberg Crude Oil [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.002%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroZeroTwoPercentageDueJuneEighteenTwoThousandFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortBloombergCrudeOilMember
[2]
Debt instrument, maturity date Jun. 18, 2015 [2]
U.S. Treasury Bills 0.015% Due 06/25/15 [Member] | ProShares UltraShort Bloomberg Crude Oil [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.015%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroOneFivePercentageDueJuneTwentyFiveTwoThousandFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortBloombergCrudeOilMember
[2]
Debt instrument, maturity date Jun. 25, 2015 [2]
U.S. Treasury Bills 0.015% Due 06/25/15 [Member] | ProShares UltraShort Bloomberg Natural Gas [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.015%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroOneFivePercentageDueJuneTwentyFiveTwoThousandFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortBloombergNaturalGasMember
Debt instrument, maturity date Jun. 25, 2015
U.S. Treasury Bills 0.015% Due 06/25/15 [Member] | ProShares Short Euro [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.015%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroOneFivePercentageDueJuneTwentyFiveTwoThousandFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesShortEuroMember
Debt instrument, maturity date Jun. 25, 2015
U.S. Treasury Bills 0.015% Due 06/25/15 [Member] | ProShares UltraShort Australian Dollar [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.015%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroOneFivePercentageDueJuneTwentyFiveTwoThousandFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortAustralianDollarMember
Debt instrument, maturity date Jun. 25, 2015
U.S. Treasury Bills 0.015% Due 06/25/15 [Member] | ProShares Ultra Euro [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.015%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroOneFivePercentageDueJuneTwentyFiveTwoThousandFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraEuroMember
Debt instrument, maturity date Jun. 25, 2015
U.S. Treasury Bills 0.023% Due 07/02/15 [Member] | ProShares UltraShort Bloomberg Crude Oil [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.023%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroTwoThreePercentageDueJulyTwoTwoThousandFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortBloombergCrudeOilMember
[2]
Debt instrument, maturity date Jul. 02, 2015 [2]
U.S. Treasury Bills 0.029% Due 07/16/15 [Member] | ProShares UltraShort Bloomberg Crude Oil [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.029%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroTwoNinePercentageDueJulySixteenTwoThousandFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortBloombergCrudeOilMember
[2]
Debt instrument, maturity date Jul. 16, 2015 [2]
U.S. Treasury Bills 0.037% Due 07/23/15 [Member] | ProShares UltraShort Bloomberg Crude Oil [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.037%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroThreeSevenPercentageDueJulyTwentyThreeTwoThousandFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortBloombergCrudeOilMember
[2]
Debt instrument, maturity date Jul. 23, 2015 [2]
U.S. Treasury Bills 0.035% Due 07/30/15 [Member] | ProShares UltraShort Bloomberg Crude Oil [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.035%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroThreeFivePercentageDueJulyThirtyTwoThousandFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortBloombergCrudeOilMember
[2]
Debt instrument, maturity date Jul. 30, 2015 [2]
U.S. Treasury Bills 0.050% Due 08/06/15 [Member] | ProShares UltraShort Bloomberg Crude Oil [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.05%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFiveZeroPercentageDueAugustSixTwoThousandFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortBloombergCrudeOilMember
[2]
Debt instrument, maturity date Aug. 06, 2015 [2]
U.S. Treasury Bills 0.044% Due 08/13/15 [Member] | ProShares UltraShort Bloomberg Crude Oil [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.044%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFourFourPercentageDueAugustThirteenTwoThousandFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortBloombergCrudeOilMember
[2]
Debt instrument, maturity date Aug. 13, 2015 [2]
U.S. Treasury Bills 0.042% Due 04/16/15 [Member] | ProShares UltraShort Bloomberg Natural Gas [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.042%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFourTwoPercentageDueAprilSixteenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortBloombergNaturalGasMember
Debt instrument, maturity date Apr. 16, 2015
U.S. Treasury Bills 0.056% Due 04/30/15 [Member] | ProShares UltraShort Bloomberg Natural Gas [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.056%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFiveSixPercentageDueAprilThirtyTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortBloombergNaturalGasMember
Debt instrument, maturity date Apr. 30, 2015
U.S. Treasury Bills 0.044% Due 05/21/15 [Member] | ProShares UltraShort Bloomberg Natural Gas [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.044%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFourFourPercentageDueMayTwentyOneTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortBloombergNaturalGasMember
Debt instrument, maturity date May 21, 2015
U.S. Treasury Bills 0.022% Due 06/04/15 [Member] | ProShares UltraShort Bloomberg Natural Gas [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.022%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroTwoTwoPercentageDueJuneFourTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortBloombergNaturalGasMember
Debt instrument, maturity date Jun. 04, 2015
U.S. Treasury Bills 0.042% Due 04/30/15 [Member] | ProShares UltraShort Gold [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.042%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFourTwoPercentageDueAprilThirtyTwoThousandFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortGoldMember
[4]
Debt instrument, maturity date Apr. 30, 2015 [4]
U.S. Treasury Bills 0.042% Due 04/30/15 [Member] | ProShares Ultra Gold [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.042%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFourTwoPercentageDueAprilThirtyTwoThousandFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraGoldMember
[4]
Debt instrument, maturity date Apr. 30, 2015 [4]
U.S. Treasury Bills 0.056% Due 05/14/15 [Member] | ProShares UltraShort Gold [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.056%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFiveSixPercentageDueMayFourteenTwoThousandFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortGoldMember
[4]
Debt instrument, maturity date May 14, 2015 [4]
U.S. Treasury Bills 0.056% Due 05/14/15 [Member] | ProShares UltraShort Silver [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.056%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFiveSixPercentageDueMayFourteenTwoThousandFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortSilverMember
Debt instrument, maturity date May 14, 2015
U.S. Treasury Bills 0.061% Due 05/21/15 [Member] | ProShares UltraShort Gold [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.061%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroSixOnePercentageDueMayTwentyOneTwoThousandFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortGoldMember
[4]
Debt instrument, maturity date May 21, 2015 [4]
U.S. Treasury Bills 0.061% Due 05/21/15 [Member] | ProShares UltraShort Silver [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.061%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroSixOnePercentageDueMayTwentyOneTwoThousandFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortSilverMember
Debt instrument, maturity date May 21, 2015
U.S. Treasury Bills 0.005% Due 06/11/15 [Member] | ProShares UltraShort Gold [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.005%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroZeroFivePercentageDueJuneElevenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortGoldMember
Debt instrument, maturity date Jun. 11, 2015
U.S. Treasury Bills 0.060% Due 06/18/15 [Member] | ProShares UltraShort Gold [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.06%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroSixZeroPercentageDueJuneEighteenTwoThousandFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortGoldMember
Debt instrument, maturity date Jun. 18, 2015
U.S. Treasury Bills 0.060% Due 06/18/15 [Member] | ProShares Ultra Bloomberg Commodity [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.06%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroSixZeroPercentageDueJuneEighteenTwoThousandFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraBloombergCommodityMember
[3]
Debt instrument, maturity date Jun. 18, 2015 [3]
U.S. Treasury Bills 0.024% Due 07/16/15 [Member] | ProShares UltraShort Gold [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.024%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroTwoFourPercentageDueJulySixteenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortGoldMember
Debt instrument, maturity date Jul. 16, 2015
U.S. Treasury Bills 0.024% Due 07/16/15 [Member] | ProShares UltraShort Silver [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.024%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroTwoFourPercentageDueJulySixteenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortSilverMember
[4]
Debt instrument, maturity date Jul. 16, 2015 [4]
U.S. Treasury Bills 0.043% Due 08/13/15 [Member] | ProShares UltraShort Gold [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.043%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFourThreePercentageDueAugustThirteenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortGoldMember
[4]
Debt instrument, maturity date Aug. 13, 2015 [4]
U.S. Treasury Bills 0.043% Due 08/13/15 [Member] | ProShares UltraShort Australian Dollar [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.043%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFourThreePercentageDueAugustThirteenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortAustralianDollarMember
Debt instrument, maturity date Aug. 13, 2015
U.S. Treasury Bills 0.043% Due 08/13/15 [Member] | ProShares Ultra Bloomberg Commodity [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.043%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFourThreePercentageDueAugustThirteenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraBloombergCommodityMember
Debt instrument, maturity date Aug. 13, 2015
U.S. Treasury Bills 0.043% Due 08/13/15 [Member] | ProShares Ultra Yen [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.043%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFourThreePercentageDueAugustThirteenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraYenMember
[5]
Debt instrument, maturity date Aug. 13, 2015 [5]
U.S. Treasury Bills 0.054% Due 04/30/15 [Member] | ProShares UltraShort Silver [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.054%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFiveFourPercentageDueAprilThirtyTwoThousandFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortSilverMember
[4]
Debt instrument, maturity date Apr. 30, 2015 [4]
U.S. Treasury Bills 0.067% Due 06/04/15 [Member] | ProShares UltraShort Silver [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.067%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroSixSevenPercentageDueJuneFourTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortSilverMember
[4]
Debt instrument, maturity date Jun. 04, 2015 [4]
U.S. Treasury Bills 0.027% Due 06/18/15 [Member] | ProShares UltraShort Silver [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.027%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroTwoSevenPercentageDueJuneEighteenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortSilverMember
[4]
Debt instrument, maturity date Jun. 18, 2015 [4]
U.S. Treasury Bills 0.038% Due 08/13/15 [Member] | ProShares UltraShort Silver [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.038%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroThreeEightPercentageDueAugustThirteenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortSilverMember
[4]
Debt instrument, maturity date Aug. 13, 2015 [4]
U.S. Treasury Bills 0.038% Due 08/13/15 [Member] | ProShares Ultra Gold [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.038%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroThreeEightPercentageDueAugustThirteenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraGoldMember
[4]
Debt instrument, maturity date Aug. 13, 2015 [4]
U.S. Treasury Bills 0.040% Due 04/30/15 [Member] | ProShares Short Euro [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.04%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFourZeroPercentageDueAprilThirtyTwoThousandFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesShortEuroMember
Debt instrument, maturity date Apr. 30, 2015
U.S. Treasury Bills 0.040% Due 04/30/15 [Member] | ProShares Ultra Bloomberg Natural Gas [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.04%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFourZeroPercentageDueAprilThirtyTwoThousandFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraBloombergNaturalGasMember
Debt instrument, maturity date Apr. 30, 2015
U.S. Treasury Bills 0.040% Due 04/30/15 [Member] | ProShares Ultra Australian Dollar [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.04%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFourZeroPercentageDueAprilThirtyTwoThousandFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraAustralianDollarMember
Debt instrument, maturity date Apr. 30, 2015
U.S. Treasury Bills 0.073% Due 06/04/15 [Member] | ProShares Short Euro [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.073%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroSevenThreePercentageDueJuneFourTwoThousandFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesShortEuroMember
Debt instrument, maturity date Jun. 04, 2015
U.S. Treasury Bills 0.073% Due 06/04/15 [Member] | ProShares UltraShort Euro [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.073%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroSevenThreePercentageDueJuneFourTwoThousandFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortEuroMember
[5]
Debt instrument, maturity date Jun. 04, 2015 [5]
U.S. Treasury Bills 0.010% Due 06/18/15 [Member] | ProShares Short Euro [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.01%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroOneZeroPercentageDueJuneEighteenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesShortEuroMember
Debt instrument, maturity date Jun. 18, 2015
U.S. Treasury Bills 0.010% Due 06/18/15 [Member] | ProShares Ultra Yen [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.01%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroOneZeroPercentageDueJuneEighteenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraYenMember
[5]
Debt instrument, maturity date Jun. 18, 2015 [5]
U.S. Treasury Bills 0.035% Due 07/16/15 [Member] | ProShares Short Euro [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.035%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroThreeFivePercentageDueJulySixteenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesShortEuroMember
Debt instrument, maturity date Jul. 16, 2015
U.S. Treasury Bills 0.056% Due 04/30/15 [Member] | ProShares UltraShort Australian Dollar [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.056%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFiveSixPercentageDueAprilThirtyTwoThousandFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortAustralianDollarMember
Debt instrument, maturity date Apr. 30, 2015
U.S. Treasury Bills 0.056% Due 04/30/15 [Member] | ProShares UltraShort Yen [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.056%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFiveSixPercentageDueAprilThirtyTwoThousandFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortYenMember
[5]
Debt instrument, maturity date Apr. 30, 2015 [5]
U.S. Treasury Bills 0.022% Due 05/28/15 [Member] | ProShares UltraShort Australian Dollar [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.022%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroTwoTwoPercentageDueMayTwentyEightTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortAustralianDollarMember
Debt instrument, maturity date May 28, 2015
U.S. Treasury Bills 0.050% Due 07/02/15 [Member] | ProShares UltraShort Australian Dollar [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.05%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFiveZeroPercentageDueJulyTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortAustralianDollarMember
Debt instrument, maturity date Jul. 02, 2015
U.S. Treasury Bills 0.048% Due 04/30/15 [Member] | ProShares UltraShort Euro [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.048%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFourEightPercentageDueAprilThirtyTwoThousandFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortEuroMember
[5]
Debt instrument, maturity date Apr. 30, 2015 [5]
U.S. Treasury Bills 0.015% Due 05/14/15 [Member] | ProShares UltraShort Euro [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.015%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroOneFivePercentageDueMayFourteenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortEuroMember
Debt instrument, maturity date May 14, 2015
U.S. Treasury Bills 0.050% Due 05/21/15 [Member] | ProShares UltraShort Euro [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.05%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFiveZeroPercentageDueMayTwentyOneTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortEuroMember
Debt instrument, maturity date May 21, 2015
U.S. Treasury Bills 0.050% Due 05/21/15 [Member] | ProShares Ultra Gold [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.05%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFiveZeroPercentageDueMayTwentyOneTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraGoldMember
Debt instrument, maturity date May 21, 2015
U.S. Treasury Bills 0.070% Due 05/28/15 [Member] | ProShares UltraShort Euro [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.07%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroSevenZeroPercentageDueMayTwentyEightTwoThousandFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortEuroMember
Debt instrument, maturity date May 28, 2015
U.S. Treasury Bills 0.090% Due 06/11/15 [Member] | ProShares UltraShort Euro [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.09%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroNineZeroPercentageDueJuneElevenTwoThousandFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortEuroMember
[5]
Debt instrument, maturity date Jun. 11, 2015 [5]
U.S. Treasury Bills 0.090% Due 06/11/15 [Member] | ProShares Ultra Silver [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.09%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroNineZeroPercentageDueJuneElevenTwoThousandFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraSilverMember
Debt instrument, maturity date Jun. 11, 2015
U.S. Treasury Bills 0.025% Due 07/16/15 [Member] | ProShares UltraShort Euro [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.025%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroTwoFivePercentageDueJulySixteenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortEuroMember
Debt instrument, maturity date Jul. 16, 2015
U.S. Treasury Bills 0.041% Due 07/23/15 [Member] | ProShares UltraShort Euro [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.041%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFourOnePercentageDueJulyTwentyThreeTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortEuroMember
[5]
Debt instrument, maturity date Jul. 23, 2015 [5]
U.S. Treasury Bills 0.040% Due 08/06/15 [Member] | ProShares UltraShort Euro [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.04%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFourZeroPercentageDueAugustSixTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortEuroMember
[5]
Debt instrument, maturity date Aug. 06, 2015 [5]
U.S. Treasury Bills 0.063% Due 05/14/15 [Member] | ProShares UltraShort Yen [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.063%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroSixThreePercentageDueMayFourteenTwoThousandFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortYenMember
Debt instrument, maturity date May 14, 2015
U.S. Treasury Bills 0.063% Due 05/14/15 [Member] | ProShares Ultra Bloomberg Natural Gas [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.063%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroSixThreePercentageDueMayFourteenTwoThousandFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraBloombergNaturalGasMember
Debt instrument, maturity date May 14, 2015
U.S. Treasury Bills 0.070% Due 05/21/15 [Member] | ProShares UltraShort Yen [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.07%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroSevenZeroPercentageDueMayTwentyOneTwoThousandFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortYenMember
[5]
Debt instrument, maturity date May 21, 2015 [5]
U.S. Treasury Bills 0.087% Due 06/11/15 [Member] | ProShares UltraShort Yen [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.087%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroEightSevenPercentageDueJuneElevenTwoThousandFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortYenMember
[5]
Debt instrument, maturity date Jun. 11, 2015 [5]
U.S. Treasury Bills 0.026% Due 06/25/15 [Member] | ProShares UltraShort Yen [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.026%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroTwoSixPercentageDueJuneTwentyFiveTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortYenMember
[5]
Debt instrument, maturity date Jun. 25, 2015 [5]
U.S. Treasury Bills 0.026% Due 06/25/15 [Member] | ProShares Ultra Bloomberg Natural Gas [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.026%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroTwoSixPercentageDueJuneTwentyFiveTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraBloombergNaturalGasMember
Debt instrument, maturity date Jun. 25, 2015
U.S. Treasury Bills 0.030% due 07/02/15 [Member] | ProShares UltraShort Yen [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.03%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroThreeZeroPercentageDueJulyTwoTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortYenMember
[5]
Debt instrument, maturity date Jul. 02, 2015 [5]
U.S. Treasury Bills 0.040% Due 07/23/15 [Member] | ProShares UltraShort Yen [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.04%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFourZeroPercentageDueJulyTwentyThreeTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortYenMember
Debt instrument, maturity date Jul. 23, 2015
U.S. Treasury Bills 0.034% Due 07/30/15 [Member] | ProShares UltraShort Yen [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.034%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroThreeFourPercentageDueJulyThirtyTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortYenMember
[5]
Debt instrument, maturity date Jul. 30, 2015 [5]
U.S. Treasury Bills 0.070% Due 08/06/15 [Member] | ProShares UltraShort Yen [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.07%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroSevenZeroPercentageDueAugustSixTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltrashortYenMember
Debt instrument, maturity date Aug. 06, 2015
U.S. Treasury Bills 0.047% Due 04/30/15 [Member] | ProShares Ultra Bloomberg Commodity [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.047%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFourSevenPercentageDueAprilThirtyTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraBloombergCommodityMember
[3]
Debt instrument, maturity date Apr. 30, 2015 [3]
U.S. Treasury Bills 0.047% Due 04/30/15 [Member] | ProShares Ultra Silver [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.047%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFourSevenPercentageDueAprilThirtyTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraSilverMember
Debt instrument, maturity date Apr. 30, 2015
U.S. Treasury Bills 0.047% Due 04/30/15 [Member] | ProShares Ultra Yen [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.047%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFourSevenPercentageDueAprilThirtyTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraYenMember
[5]
Debt instrument, maturity date Apr. 30, 2015 [5]
U.S. Treasury Bills 0.038% Due 04/16/15 [Member] | ProShares Ultra Bloomberg Crude Oil [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.038%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroThreeEightPercentageDueAprilSixteenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraBloombergCrudeOilMember
Debt instrument, maturity date Apr. 16, 2015
U.S. Treasury Bills 0.035% Due 04/30/15 [Member] | ProShares Ultra Bloomberg Crude Oil [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.035%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroThreeFivePercentageDueAprilThirtyTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraBloombergCrudeOilMember
Debt instrument, maturity date Apr. 30, 2015
U.S. Treasury Bills 0.027% Due 05/21/15 [Member] | ProShares Ultra Bloomberg Crude Oil [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.027%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroTwoSevenPercentageDueMayTwentyOneTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraBloombergCrudeOilMember
[2]
Debt instrument, maturity date May 21, 2015 [2]
U.S. Treasury Bills 0.023% Due 05/28/15 [Member] | ProShares Ultra Bloomberg Crude Oil [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.023%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroTwoThreePercentageDueMayTwentyEightTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraBloombergCrudeOilMember
[2]
Debt instrument, maturity date May 28, 2015 [2]
U.S. Treasury Bills 0.027% Due 06/04/15 [Member] | ProShares Ultra Bloomberg Crude Oil [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.027%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroTwoSevenPercentageDueJuneFourTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraBloombergCrudeOilMember
Debt instrument, maturity date Jun. 04, 2015
U.S. Treasury Bills 0.007% Due 06/11/15 [Member] | ProShares Ultra Bloomberg Crude Oil [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.007%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroZeroSevenPercentageDueJuneElevenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraBloombergCrudeOilMember
Debt instrument, maturity date Jun. 11, 2015
U.S. Treasury Bills 0.028% Due 06/18/15 [Member] | ProShares Ultra Bloomberg Crude Oil [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.028%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroTwoEightPercentageDueJuneEighteenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraBloombergCrudeOilMember
[2]
Debt instrument, maturity date Jun. 18, 2015 [2]
U.S. Treasury Bills 0.045% Due 06/25/15 [Member] | ProShares Ultra Bloomberg Crude Oil [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.045%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFourFivePercentageDueJuneTwentyFiveTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraBloombergCrudeOilMember
[2]
Debt instrument, maturity date Jun. 25, 2015 [2]
U.S. Treasury Bills 0.027% Due 07/02/15 [Member] | ProShares Ultra Bloomberg Crude Oil [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.027%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroTwoSevenPercentageDueJulyTwoTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraBloombergCrudeOilMember
[2]
Debt instrument, maturity date Jul. 02, 2015 [2]
U.S. Treasury Bills 0.034% Due 07/09/15 [Member] | ProShares Ultra Bloomberg Crude Oil [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.034%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroThreeFourPercentageDueJulyNineTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraBloombergCrudeOilMember
[2]
Debt instrument, maturity date Jul. 09, 2015 [2]
U.S. Treasury Bills 0.030% Due 07/23/15 [Member] | ProShares Ultra Bloomberg Crude Oil [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.03%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroThreeZeroPercentageDueJulyTwentyThreeTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraBloombergCrudeOilMember
[2]
Debt instrument, maturity date Jul. 23, 2015 [2]
U.S. Treasury Bills 0.029% Due 07/30/15 [Member] | ProShares Ultra Bloomberg Crude Oil [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.029%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroTwoNinePercentageDueJulyThirtyTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraBloombergCrudeOilMember
[2]
Debt instrument, maturity date Jul. 30, 2015 [2]
U.S. Treasury Bills 0.051% Due 08/06/15 [Member] | ProShares Ultra Bloomberg Crude Oil [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.051%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFiveOnePercentageDueAugustSixTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraBloombergCrudeOilMember
[2]
Debt instrument, maturity date Aug. 06, 2015 [2]
U.S. Treasury Bills 0.052% Due 05/28/15 [Member] | ProShares Ultra Bloomberg Natural Gas [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.052%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFiveTwoPercentageDueMayTwentyEightThousandFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraBloombergNaturalGasMember
Debt instrument, maturity date May 28, 2015
U.S. Treasury Bills 0.026% Due 06/18/15 [Member] | ProShares Ultra Bloomberg Natural Gas [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.026%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroTwoSixPercentageDueJuneEighteenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraBloombergNaturalGasMember
Debt instrument, maturity date Jun. 18, 2015
U.S. Treasury Bills 0.047% Due 07/02/15 [Member] | ProShares Ultra Bloomberg Natural Gas [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.047%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFourSevenPercentageDueJulyTwoTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraBloombergNaturalGasMember
Debt instrument, maturity date Jul. 02, 2015
U.S. Treasury Bills 0.042% Due 07/09/15 [Member] | ProShares Ultra Bloomberg Natural Gas [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.042%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFourTwoPercentageDueJulyNineTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraBloombergNaturalGasMember
Debt instrument, maturity date Jul. 09, 2015
U.S. Treasury Bills 0.039% Due 08/13/15 [Member] | ProShares Ultra Bloomberg Natural Gas [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.039%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroThreeNinePercentageDueAugustThirteenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraBloombergNaturalGasMember
[1]
Debt instrument, maturity date Aug. 13, 2015 [1]
U.S. Treasury Bills 0.039% Due 08/13/15 [Member] | ProShares Ultra Silver [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.039%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroThreeNinePercentageDueAugustThirteenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraSilverMember
[4]
Debt instrument, maturity date Aug. 13, 2015 [4]
U.S. Treasury Bills 0.058% Due 05/14/15 [Member] | ProShares Ultra Gold [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.058%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFiveEightPercentageDueMayFourteenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraGoldMember
[4]
Debt instrument, maturity date May 14, 2015 [4]
U.S. Treasury Bills 0.078% Due 06/04/15 [Member] | ProShares Ultra Gold [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.078%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroSevenEightPercentageDueJuneFourTwoThousandFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraGoldMember
[4]
Debt instrument, maturity date Jun. 04, 2015 [4]
U.S. Treasury Bills 0.078% Due 06/04/15 [Member] | ProShares Ultra Silver [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.078%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroSevenEightPercentageDueJuneFourTwoThousandFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraSilverMember
[4]
Debt instrument, maturity date Jun. 04, 2015 [4]
U.S. Treasury Bills 0.058% Due 06/18/15 [Member] | ProShares Ultra Gold [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.058%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFiveEightPercentageDueJuneEighteenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraGoldMember
[4]
Debt instrument, maturity date Jun. 18, 2015 [4]
U.S. Treasury Bills 0.037% Due 07/02/15 [Member] | ProShares Ultra Gold [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.037%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroThreeSevenPercentageDueJulyTwoTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraGoldMember
[4]
Debt instrument, maturity date Jul. 02, 2015 [4]
U.S. Treasury Bills 0.004% Due 05/21/15 [Member] | ProShares Ultra Silver [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.004%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroZeroFourPercentageDueMayTwentyOneTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraSilverMember
Debt instrument, maturity date May 21, 2015
U.S. Treasury Bills 0.015% Due 05/28/15 [Member] | ProShares Ultra Silver [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.015%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroOneFivePercentageDueMayTwentyEightTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraSilverMember
Debt instrument, maturity date May 28, 2015
U.S. Treasury Bills 0.015% Due 05/28/15 [Member] | ProShares Ultra Euro [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.015%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroOneFivePercentageDueMayTwentyEightTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraEuroMember
Debt instrument, maturity date May 28, 2015
U.S. Treasury Bills 0.045% Due 06/18/15 [Member] | ProShares Ultra Silver [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.045%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFourFivePercentageDueJuneEighteenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraSilverMember
Debt instrument, maturity date Jun. 18, 2015
U.S. Treasury Bills 0.038% Due 07/02/15 [Member] | ProShares Ultra Silver [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.038%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroThreeEightPercentageDueJulyTwoTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraSilverMember
[4]
Debt instrument, maturity date Jul. 02, 2015 [4]
U.S. Treasury Bills 0.020% Due 07/16/15 [Member] | ProShares Ultra Silver [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.02%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroTwoZeroPercentageDueJulySixteenTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraSilverMember
Debt instrument, maturity date Jul. 16, 2015
U.S. Treasury Bills 0.035% Due 07/23/15 [Member] | ProShares Ultra Silver [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.035%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroThreeFivePercentageDueJulyTwentyThreeTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraSilverMember
Debt instrument, maturity date Jul. 23, 2015
U.S. Treasury Bills 0.066% Due 08/06/15 [Member] | ProShares Ultra Silver [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.066%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroSixSixPercentageDueAugustSixTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraSilverMember
[4]
Debt instrument, maturity date Aug. 06, 2015 [4]
U.S. Treasury Bills 0.034% Due 04/30/15 [Member] | ProShares Ultra Euro [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.034%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroThreeFourPercentageDueAprilThirtyTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraEuroMember
[5]
Debt instrument, maturity date Apr. 30, 2015 [5]
U.S. Treasury Bills 0.035% Due 05/21/15 [Member] | ProShares Ultra Euro [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.035%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroThreeFivePercentageDueMayTwentyOneTwoThousandFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraEuroMember
Debt instrument, maturity date May 21, 2015
U.S. Treasury Bills 0.041% Due 07/02/15 [Member] | ProShares Ultra Euro [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.041%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroFourOnePercentageDueJulyTwoTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraEuroMember
[5]
Debt instrument, maturity date Jul. 02, 2015 [5]
U.S. Treasury Bills 0.034% Due 07/23/15 [Member] | ProShares Ultra Euro [Member]  
Schedule of Investments [Line Items]  
Interest rate 0.034%us-gaap_DebtInstrumentInterestRateStatedPercentage
/ us-gaap_InvestmentTypeAxis
= ck0001415311_UsTreasuryBillsZeroPointZeroThreeFourPercentageDueJulyTwentyThreeTwoThousandAndFifteenMember
/ us-gaap_StatementBusinessSegmentsAxis
= ck0001415311_ProsharesUltraEuroMember
[5]
Debt instrument, maturity date Jul. 23, 2015 [5]
[1] All or partial amount pledged as collateral for futures contracts.
[2] All or partial amount pledged as collateral for swap agreements and/or futures contracts.
[3] All or partial amount pledged as collateral for swap agreements.
[4] All or partial amount pledged as collateral for forward agreements and/or futures contracts.
[5] All or partial amount segregated as collateral for foreign currency forward contracts.