v2.4.1.9

Significant Accounting Policies - Valuation of Investments using Fair Value Hierarchy (Detail) (USD $)	Mar. 31, 2015	Dec. 31, 2014
ProShares Managed Futures Strategy [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	$ 83,233us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesManagedFuturesStrategyMember	$ 104,327us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesManagedFuturesStrategyMember
ProShares VIX Short-Term Futures ETF [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	126,077,909us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesVixShortTermFuturesEtfMember	88,352,919us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesVixShortTermFuturesEtfMember
ProShares VIX Mid-Term Futures ETF [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	27,175,022us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesVixMidTermFuturesEtfMember	24,366,571us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesVixMidTermFuturesEtfMember
ProShares Short VIX Short-Term Futures ETF [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	229,911,927us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesShortVixShortTermFuturesEtfMember	430,623,071us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesShortVixShortTermFuturesEtfMember
ProShares Ultra VIX Short-Term Futures ETF [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	520,974,371us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraVixShortTermFuturesEtfMember	222,224,441us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraVixShortTermFuturesEtfMember
ProShares UltraShort Bloomberg Commodity [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	5,267,452us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortBloombergCommodityMember	4,800,807us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortBloombergCommodityMember
ProShares UltraShort Bloomberg Crude Oil [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	363,997,731us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortBloombergCrudeOilMember	174,419,288us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortBloombergCrudeOilMember
ProShares UltraShort Bloomberg Natural Gas [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	9,839,238us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortBloombergNaturalGasMember	12,614,175us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortBloombergNaturalGasMember
ProShares UltraShort Gold [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	77,850,098us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortGoldMember	81,752,809us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortGoldMember
ProShares UltraShort Silver [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	46,268,582us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortSilverMember	52,823,205us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortSilverMember
ProShares Short Euro [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	18,121,948us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesShortEuroMember	12,471,908us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesShortEuroMember
ProShares UltraShort Australian Dollar [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	17,352,343us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortAustralianDollarMember	21,011,160us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortAustralianDollarMember
ProShares UltraShort Euro [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	572,841,626us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortEuroMember	503,874,111us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortEuroMember
ProShares UltraShort Yen [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	444,758,540us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortYenMember	531,378,971us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortYenMember
ProShares Ultra Bloomberg Commodity [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	2,113,376us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraBloombergCommodityMember	2,423,562us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraBloombergCommodityMember
ProShares Ultra Bloomberg Crude Oil [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	923,776,509us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraBloombergCrudeOilMember	344,544,852us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraBloombergCrudeOilMember
ProShares Ultra Bloomberg Natural Gas [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	49,732,210us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraBloombergNaturalGasMember	18,520,944us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraBloombergNaturalGasMember
ProShares Ultra Gold [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	95,901,574us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraGoldMember	103,983,591us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraGoldMember
ProShares Ultra Silver [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	317,119,181us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraSilverMember	293,077,531us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraSilverMember
ProShares Ultra Australian Dollar [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	2,144,506us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraAustralianDollarMember	2,308,860us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraAustralianDollarMember
ProShares Ultra Euro [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	14,464,119us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraEuroMember	2,312,327us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraEuroMember
ProShares Ultra Yen [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	5,169,013us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraYenMember	1,272,624us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraYenMember
Total Trust [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	3,870,940,508us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_TrustMember	2,929,262,054us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_TrustMember
Level I - Quoted Prices [Member] | Short-Term U.S. Government and Agencies [Member] | ProShares VIX Short-Term Futures ETF [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	131,184,020us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentShorttermDebtSecuritiesMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesVixShortTermFuturesEtfMember	82,088,299us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentShorttermDebtSecuritiesMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesVixShortTermFuturesEtfMember
Level I - Quoted Prices [Member] | Short-Term U.S. Government and Agencies [Member] | ProShares VIX Mid-Term Futures ETF [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	27,675,412us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentShorttermDebtSecuritiesMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesVixMidTermFuturesEtfMember	24,105,906us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentShorttermDebtSecuritiesMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesVixMidTermFuturesEtfMember
Level I - Quoted Prices [Member] | Short-Term U.S. Government and Agencies [Member] | ProShares Short VIX Short-Term Futures ETF [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	222,919,943us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentShorttermDebtSecuritiesMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesShortVixShortTermFuturesEtfMember	446,975,220us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentShorttermDebtSecuritiesMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesShortVixShortTermFuturesEtfMember
Level I - Quoted Prices [Member] | Short-Term U.S. Government and Agencies [Member] | ProShares Ultra VIX Short-Term Futures ETF [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	569,900,064us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentShorttermDebtSecuritiesMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraVixShortTermFuturesEtfMember	182,639,188us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentShorttermDebtSecuritiesMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraVixShortTermFuturesEtfMember
Level I - Quoted Prices [Member] | Short-Term U.S. Government and Agencies [Member] | ProShares UltraShort Bloomberg Commodity [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	4,990,827us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentShorttermDebtSecuritiesMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortBloombergCommodityMember	4,233,548us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentShorttermDebtSecuritiesMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortBloombergCommodityMember
Level I - Quoted Prices [Member] | Short-Term U.S. Government and Agencies [Member] | ProShares UltraShort Bloomberg Crude Oil [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	319,733,997us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentShorttermDebtSecuritiesMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortBloombergCrudeOilMember	131,594,608us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentShorttermDebtSecuritiesMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortBloombergCrudeOilMember
Level I - Quoted Prices [Member] | Short-Term U.S. Government and Agencies [Member] | ProShares UltraShort Bloomberg Natural Gas [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	8,979,498us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentShorttermDebtSecuritiesMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortBloombergNaturalGasMember	8,672,710us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentShorttermDebtSecuritiesMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortBloombergNaturalGasMember
Level I - Quoted Prices [Member] | Short-Term U.S. Government and Agencies [Member] | ProShares UltraShort Gold [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	79,438,219us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentShorttermDebtSecuritiesMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortGoldMember	84,040,107us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentShorttermDebtSecuritiesMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortGoldMember
Level I - Quoted Prices [Member] | Short-Term U.S. Government and Agencies [Member] | ProShares UltraShort Silver [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	50,001,670us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentShorttermDebtSecuritiesMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortSilverMember	52,226,692us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentShorttermDebtSecuritiesMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortSilverMember
Level I - Quoted Prices [Member] | Short-Term U.S. Government and Agencies [Member] | ProShares Short Euro [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	18,012,179us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentShorttermDebtSecuritiesMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesShortEuroMember	12,086,577us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentShorttermDebtSecuritiesMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesShortEuroMember
Level I - Quoted Prices [Member] | Short-Term U.S. Government and Agencies [Member] | ProShares UltraShort Australian Dollar [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	16,932,493us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentShorttermDebtSecuritiesMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortAustralianDollarMember	20,267,679us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentShorttermDebtSecuritiesMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortAustralianDollarMember
Level I - Quoted Prices [Member] | Short-Term U.S. Government and Agencies [Member] | ProShares UltraShort Euro [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	549,451,431us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentShorttermDebtSecuritiesMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortEuroMember	487,111,117us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentShorttermDebtSecuritiesMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortEuroMember
Level I - Quoted Prices [Member] | Short-Term U.S. Government and Agencies [Member] | ProShares UltraShort Yen [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	444,090,783us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentShorttermDebtSecuritiesMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortYenMember	532,957,746us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentShorttermDebtSecuritiesMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortYenMember
Level I - Quoted Prices [Member] | Short-Term U.S. Government and Agencies [Member] | ProShares Ultra Bloomberg Commodity [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	2,242,809us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentShorttermDebtSecuritiesMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraBloombergCommodityMember	2,754,900us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentShorttermDebtSecuritiesMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraBloombergCommodityMember
Level I - Quoted Prices [Member] | Short-Term U.S. Government and Agencies [Member] | ProShares Ultra Bloomberg Crude Oil [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	1,066,114,169us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentShorttermDebtSecuritiesMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraBloombergCrudeOilMember	467,200,736us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentShorttermDebtSecuritiesMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraBloombergCrudeOilMember
Level I - Quoted Prices [Member] | Short-Term U.S. Government and Agencies [Member] | ProShares Ultra Bloomberg Natural Gas [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	57,169,841us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentShorttermDebtSecuritiesMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraBloombergNaturalGasMember	53,410,227us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentShorttermDebtSecuritiesMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraBloombergNaturalGasMember
Level I - Quoted Prices [Member] | Short-Term U.S. Government and Agencies [Member] | ProShares Ultra Gold [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	94,234,586us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentShorttermDebtSecuritiesMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraGoldMember	101,927,857us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentShorttermDebtSecuritiesMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraGoldMember
Level I - Quoted Prices [Member] | Short-Term U.S. Government and Agencies [Member] | ProShares Ultra Silver [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	294,501,633us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentShorttermDebtSecuritiesMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraSilverMember	305,474,211us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentShorttermDebtSecuritiesMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraSilverMember
Level I - Quoted Prices [Member] | Short-Term U.S. Government and Agencies [Member] | ProShares Ultra Australian Dollar [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	2,201,920us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentShorttermDebtSecuritiesMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraAustralianDollarMember	2,405,685us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentShorttermDebtSecuritiesMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraAustralianDollarMember
Level I - Quoted Prices [Member] | Short-Term U.S. Government and Agencies [Member] | ProShares Ultra Euro [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	15,242,869us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentShorttermDebtSecuritiesMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraEuroMember	2,415,698us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentShorttermDebtSecuritiesMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraEuroMember
Level I - Quoted Prices [Member] | Short-Term U.S. Government and Agencies [Member] | ProShares Ultra Yen [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	5,210,191us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentShorttermDebtSecuritiesMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraYenMember	1,287,869us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentShorttermDebtSecuritiesMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraYenMember
Level I - Quoted Prices [Member] | Short-Term U.S. Government and Agencies [Member] | Total Trust [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	3,980,228,554us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentShorttermDebtSecuritiesMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_TrustMember	3,005,876,580us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_USTreasuryAndGovernmentShorttermDebtSecuritiesMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_TrustMember
Level I - Quoted Prices [Member] | VIX Futures Contracts [Member] | ProShares Managed Futures Strategy [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	83,233us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_FutureMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesManagedFuturesStrategyMember	104,327us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_FutureMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesManagedFuturesStrategyMember
Level I - Quoted Prices [Member] | VIX Futures Contracts [Member] | ProShares VIX Short-Term Futures ETF [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	(5,106,111)us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_FutureMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesVixShortTermFuturesEtfMember	6,264,620us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_FutureMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesVixShortTermFuturesEtfMember
Level I - Quoted Prices [Member] | VIX Futures Contracts [Member] | ProShares VIX Mid-Term Futures ETF [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	(500,390)us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_FutureMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesVixMidTermFuturesEtfMember	260,665us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_FutureMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesVixMidTermFuturesEtfMember
Level I - Quoted Prices [Member] | VIX Futures Contracts [Member] | ProShares Short VIX Short-Term Futures ETF [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	6,991,984us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_FutureMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesShortVixShortTermFuturesEtfMember	(16,352,149)us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_FutureMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesShortVixShortTermFuturesEtfMember
Level I - Quoted Prices [Member] | VIX Futures Contracts [Member] | ProShares Ultra VIX Short-Term Futures ETF [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	(48,925,693)us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_FutureMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraVixShortTermFuturesEtfMember	39,585,253us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_FutureMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraVixShortTermFuturesEtfMember
Level I - Quoted Prices [Member] | VIX Futures Contracts [Member] | ProShares UltraShort Bloomberg Crude Oil [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	17,406,261us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_FutureMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortBloombergCrudeOilMember	15,806,603us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_FutureMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortBloombergCrudeOilMember
Level I - Quoted Prices [Member] | VIX Futures Contracts [Member] | ProShares UltraShort Bloomberg Natural Gas [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	859,740us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_FutureMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortBloombergNaturalGasMember	3,941,465us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_FutureMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortBloombergNaturalGasMember
Level I - Quoted Prices [Member] | VIX Futures Contracts [Member] | ProShares UltraShort Gold [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	(6,040)us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_FutureMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortGoldMember	(4,520)us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_FutureMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortGoldMember
Level I - Quoted Prices [Member] | VIX Futures Contracts [Member] | ProShares UltraShort Silver [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	3,095us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_FutureMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortSilverMember	1,560us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_FutureMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortSilverMember
Level I - Quoted Prices [Member] | VIX Futures Contracts [Member] | ProShares Short Euro [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	109,769us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_FutureMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesShortEuroMember	385,331us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_FutureMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesShortEuroMember
Level I - Quoted Prices [Member] | VIX Futures Contracts [Member] | ProShares UltraShort Australian Dollar [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	419,850us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_FutureMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortAustralianDollarMember	743,481us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_FutureMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortAustralianDollarMember
Level I - Quoted Prices [Member] | VIX Futures Contracts [Member] | ProShares Ultra Bloomberg Crude Oil [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	(63,863,441)us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_FutureMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraBloombergCrudeOilMember	(46,474,787)us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_FutureMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraBloombergCrudeOilMember
Level I - Quoted Prices [Member] | VIX Futures Contracts [Member] | ProShares Ultra Bloomberg Natural Gas [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	(7,437,631)us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_FutureMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraBloombergNaturalGasMember	(34,889,283)us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_FutureMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraBloombergNaturalGasMember
Level I - Quoted Prices [Member] | VIX Futures Contracts [Member] | ProShares Ultra Gold [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	6,020us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_FutureMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraGoldMember	4,580us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_FutureMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraGoldMember
Level I - Quoted Prices [Member] | VIX Futures Contracts [Member] | ProShares Ultra Silver [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	(3,320)us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_FutureMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraSilverMember	(1,560)us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_FutureMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraSilverMember
Level I - Quoted Prices [Member] | VIX Futures Contracts [Member] | ProShares Ultra Australian Dollar [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	(57,414)us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_FutureMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraAustralianDollarMember	(96,825)us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_FutureMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraAustralianDollarMember
Level I - Quoted Prices [Member] | VIX Futures Contracts [Member] | Total Trust [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	(100,020,088)us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_FutureMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_TrustMember	(30,721,239)us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel1Member / us-gaap_InvestmentTypeAxis = us-gaap_FutureMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_TrustMember
Level II - Other Significant Observable Inputs [Member] | Forward Agreements [Member] | ProShares UltraShort Gold [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	(1,582,081)us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = us-gaap_ForwardContractsMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortGoldMember	(2,282,778)us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = us-gaap_ForwardContractsMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortGoldMember
Level II - Other Significant Observable Inputs [Member] | Forward Agreements [Member] | ProShares UltraShort Silver [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	(3,736,183)us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = us-gaap_ForwardContractsMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortSilverMember	594,953us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = us-gaap_ForwardContractsMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortSilverMember
Level II - Other Significant Observable Inputs [Member] | Forward Agreements [Member] | ProShares Ultra Gold [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	1,660,968us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = us-gaap_ForwardContractsMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraGoldMember	2,051,154us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = us-gaap_ForwardContractsMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraGoldMember
Level II - Other Significant Observable Inputs [Member] | Forward Agreements [Member] | ProShares Ultra Silver [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	22,620,868us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = us-gaap_ForwardContractsMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraSilverMember	(12,395,120)us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = us-gaap_ForwardContractsMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraSilverMember
Level II - Other Significant Observable Inputs [Member] | Forward Agreements [Member] | Total Trust [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	18,963,572us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = us-gaap_ForwardContractsMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_TrustMember	(12,031,791)us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = us-gaap_ForwardContractsMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_TrustMember
Level II - Other Significant Observable Inputs [Member] | Foreign Currency Forward Contracts [Member] | ProShares UltraShort Euro [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	23,390,195us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = us-gaap_ForeignExchangeForwardMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortEuroMember	16,762,994us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = us-gaap_ForeignExchangeForwardMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortEuroMember
Level II - Other Significant Observable Inputs [Member] | Foreign Currency Forward Contracts [Member] | ProShares UltraShort Yen [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	667,757us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = us-gaap_ForeignExchangeForwardMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortYenMember	(1,578,775)us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = us-gaap_ForeignExchangeForwardMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortYenMember
Level II - Other Significant Observable Inputs [Member] | Foreign Currency Forward Contracts [Member] | ProShares Ultra Euro [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	(778,750)us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = us-gaap_ForeignExchangeForwardMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraEuroMember	(103,371)us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = us-gaap_ForeignExchangeForwardMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraEuroMember
Level II - Other Significant Observable Inputs [Member] | Foreign Currency Forward Contracts [Member] | ProShares Ultra Yen [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	(41,178)us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = us-gaap_ForeignExchangeForwardMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraYenMember	(15,245)us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = us-gaap_ForeignExchangeForwardMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltraYenMember
Level II - Other Significant Observable Inputs [Member] | Foreign Currency Forward Contracts [Member] | Total Trust [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	23,238,024us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = us-gaap_ForeignExchangeForwardMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_TrustMember	15,065,603us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = us-gaap_ForeignExchangeForwardMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_TrustMember
Level II - Other Significant Observable Inputs [Member] | Swap Agreements [Member] | ProShares UltraShort Bloomberg Commodity [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	276,625us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = us-gaap_SwapMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortBloombergCommodityMember	567,259us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = us-gaap_SwapMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortBloombergCommodityMember
Level II - Other Significant Observable Inputs [Member] | Swap Agreements [Member] | ProShares UltraShort Bloomberg Crude Oil [Member]
Significant Accounting Policies [Line Items]
Investments, fair value disclosure	26,857,473us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = us-gaap_SwapMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortBloombergCrudeOilMember	27,018,077us-gaap_AlternativeInvestmentsFairValueDisclosure / us-gaap_FairValueByFairValueHierarchyLevelAxis = us-gaap_FairValueInputsLevel2Member / us-gaap_InvestmentTypeAxis = us-gaap_SwapMember / us-gaap_StatementBusinessSegmentsAxis = ck0001415311_ProsharesUltrashortBloombergCrudeOilMember
Level II - Other Significant Observable Inputs [Member] | Swap Agreements [Member] | ProShares Ultra Bloomberg Commodity [Member]
Significant Accounting Policies [Line Items]
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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=36462937&loc=d3e19207-110258



Reference 2: http://www.xbrl.org/2003/role/presentationRef

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