<?xml version='1.0' encoding='UTF-8'?>
<FilingSummary>
  <Version>3.6.0.2</Version>
  <ProcessingTime/>
  <ReportFormat>html</ReportFormat>
  <ContextCount>1343</ContextCount>
  <ElementCount>176</ElementCount>
  <EntityCount>1</EntityCount>
  <FootnotesReported>true</FootnotesReported>
  <SegmentCount>272</SegmentCount>
  <ScenarioCount>0</ScenarioCount>
  <TuplesReported>false</TuplesReported>
  <UnitCount>9</UnitCount>
  <MyReports>
    <Report instance="ck0001415311-20161231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R1.htm</HtmlFileName>
      <LongName>101 - Document - Document and Entity Information</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.proshares.com/taxonomy/role/DocumentandEntityInformation</Role>
      <ShortName>Document and Entity Information</ShortName>
      <MenuCategory>Cover</MenuCategory>
      <Position>1</Position>
    </Report>
    <Report instance="ck0001415311-20161231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R2.htm</HtmlFileName>
      <LongName>103 - Statement - Statements of Financial Condition</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.proshares.com/taxonomy/role/StatementOfFinancialPositionUnclassified-DepositBasedOperations</Role>
      <ShortName>Statements of Financial Condition</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>2</Position>
    </Report>
    <Report instance="ck0001415311-20161231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R3.htm</HtmlFileName>
      <LongName>104 - Statement - Statements of Financial Condition (Parenthetical)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.proshares.com/taxonomy/role/StatementOfFinancialPositionUnclassified-DepositBasedOperationsParenthetical</Role>
      <ShortName>Statements of Financial Condition (Parenthetical)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>3</Position>
    </Report>
    <Report instance="ck0001415311-20161231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R4.htm</HtmlFileName>
      <LongName>105 - Statement - Statements of Operations</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.proshares.com/taxonomy/role/StatementOfIncomeInterestBasedRevenue</Role>
      <ShortName>Statements of Operations</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>4</Position>
    </Report>
    <Report instance="ck0001415311-20161231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R5.htm</HtmlFileName>
      <LongName>106 - Statement - Statements of Changes in Shareholders' Equity</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.proshares.com/taxonomy/role/StatementOfShareholdersEquityAndOtherComprehensiveIncome</Role>
      <ShortName>Statements of Changes in Shareholders' Equity</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>5</Position>
    </Report>
    <Report instance="ck0001415311-20161231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R6.htm</HtmlFileName>
      <LongName>107 - Statement - Statements of Changes in Shareholders' Equity (Parenthetical)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.proshares.com/taxonomy/role/StatementOfShareholdersEquityAndOtherComprehensiveIncomeParenthetical</Role>
      <ShortName>Statements of Changes in Shareholders' Equity (Parenthetical)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>6</Position>
    </Report>
    <Report instance="ck0001415311-20161231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R7.htm</HtmlFileName>
      <LongName>108 - Statement - Statements of Cash Flows</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.proshares.com/taxonomy/role/StatementOfCashFlowsIndirectDepositBasedOperations</Role>
      <ShortName>Statements of Cash Flows</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>7</Position>
    </Report>
    <Report instance="ck0001415311-20161231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R8.htm</HtmlFileName>
      <LongName>109 - Disclosure - Organization</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.proshares.com/taxonomy/role/NotesToFinancialStatementsOrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlock</Role>
      <ShortName>Organization</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>8</Position>
    </Report>
    <Report instance="ck0001415311-20161231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R9.htm</HtmlFileName>
      <LongName>110 - Disclosure - Significant Accounting Policies</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.proshares.com/taxonomy/role/NotesToFinancialStatementsSignificantAccountingPoliciesTextBlock</Role>
      <ShortName>Significant Accounting Policies</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>9</Position>
    </Report>
    <Report instance="ck0001415311-20161231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R10.htm</HtmlFileName>
      <LongName>111 - Disclosure - Investments</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.proshares.com/taxonomy/role/NotesToFinancialStatementsInvestmentsInDebtAndMarketableEquitySecuritiesAndCertainTradingAssetsDisclosureTextBlock</Role>
      <ShortName>Investments</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>10</Position>
    </Report>
    <Report instance="ck0001415311-20161231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R11.htm</HtmlFileName>
      <LongName>112 - Disclosure - Agreements</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.proshares.com/taxonomy/role/NotesToFinancialStatementsAgreementsTextBlock</Role>
      <ShortName>Agreements</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>11</Position>
    </Report>
    <Report instance="ck0001415311-20161231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R12.htm</HtmlFileName>
      <LongName>113 - Disclosure - Offering Costs</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.proshares.com/taxonomy/role/NotesToFinancialStatementsOfferingCostsTextBlock</Role>
      <ShortName>Offering Costs</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>12</Position>
    </Report>
    <Report instance="ck0001415311-20161231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R13.htm</HtmlFileName>
      <LongName>114 - Disclosure - Creation and Redemption of Creation Units</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.proshares.com/taxonomy/role/NotesToFinancialStatementsCreationAndRedemptionOfCreationUnitsTextBlock</Role>
      <ShortName>Creation and Redemption of Creation Units</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>13</Position>
    </Report>
    <Report instance="ck0001415311-20161231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R14.htm</HtmlFileName>
      <LongName>115 - Disclosure - Financial Highlights</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.proshares.com/taxonomy/role/NotesToFinancialStatementsQuarterlyFinancialInformationTextBlock</Role>
      <ShortName>Financial Highlights</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>14</Position>
    </Report>
    <Report instance="ck0001415311-20161231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R15.htm</HtmlFileName>
      <LongName>116 - Disclosure - Risk</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.proshares.com/taxonomy/role/NotesToFinancialStatementsConcentrationRiskDisclosureTextBlock</Role>
      <ShortName>Risk</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>15</Position>
    </Report>
    <Report instance="ck0001415311-20161231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R16.htm</HtmlFileName>
      <LongName>117 - Disclosure - Subsequent Events</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.proshares.com/taxonomy/role/NotesToFinancialStatementsSubsequentEventsTextBlock</Role>
      <ShortName>Subsequent Events</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>16</Position>
    </Report>
    <Report instance="ck0001415311-20161231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R17.htm</HtmlFileName>
      <LongName>118 - Disclosure - Significant Accounting Policies (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.proshares.com/taxonomy/role/NotesToFinancialStatementsSignificantAccountingPoliciesTextBlockPolicies</Role>
      <ShortName>Significant Accounting Policies (Policies)</ShortName>
      <MenuCategory>Policies</MenuCategory>
      <ParentRole>http://www.proshares.com/taxonomy/role/NotesToFinancialStatementsSignificantAccountingPoliciesTextBlock</ParentRole>
      <Position>17</Position>
    </Report>
    <Report instance="ck0001415311-20161231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R18.htm</HtmlFileName>
      <LongName>119 - Disclosure - Organization (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.proshares.com/taxonomy/role/NotesToFinancialStatementsOrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlockTables</Role>
      <ShortName>Organization (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.proshares.com/taxonomy/role/NotesToFinancialStatementsOrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureTextBlock</ParentRole>
      <Position>18</Position>
    </Report>
    <Report instance="ck0001415311-20161231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R19.htm</HtmlFileName>
      <LongName>120 - Disclosure - Significant Accounting Policies (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.proshares.com/taxonomy/role/NotesToFinancialStatementsSignificantAccountingPoliciesTextBlockTables</Role>
      <ShortName>Significant Accounting Policies (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.proshares.com/taxonomy/role/NotesToFinancialStatementsSignificantAccountingPoliciesTextBlock</ParentRole>
      <Position>19</Position>
    </Report>
    <Report instance="ck0001415311-20161231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R20.htm</HtmlFileName>
      <LongName>121 - Disclosure - Investments (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.proshares.com/taxonomy/role/NotesToFinancialStatementsInvestmentsInDebtAndMarketableEquitySecuritiesAndCertainTradingAssetsDisclosureTextBlockTables</Role>
      <ShortName>Investments (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.proshares.com/taxonomy/role/NotesToFinancialStatementsInvestmentsInDebtAndMarketableEquitySecuritiesAndCertainTradingAssetsDisclosureTextBlock</ParentRole>
      <Position>20</Position>
    </Report>
    <Report instance="ck0001415311-20161231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R21.htm</HtmlFileName>
      <LongName>122 - Disclosure - Creation and Redemption of Creation Units (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.proshares.com/taxonomy/role/NotesToFinancialStatementsCreationAndRedemptionOfCreationUnitsTextBlockTables</Role>
      <ShortName>Creation and Redemption of Creation Units (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.proshares.com/taxonomy/role/NotesToFinancialStatementsCreationAndRedemptionOfCreationUnitsTextBlock</ParentRole>
      <Position>21</Position>
    </Report>
    <Report instance="ck0001415311-20161231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R22.htm</HtmlFileName>
      <LongName>123 - Disclosure - Financial Highlights (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.proshares.com/taxonomy/role/NotesToFinancialStatementsQuarterlyFinancialInformationTextBlockTables</Role>
      <ShortName>Financial Highlights (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.proshares.com/taxonomy/role/NotesToFinancialStatementsQuarterlyFinancialInformationTextBlock</ParentRole>
      <Position>22</Position>
    </Report>
    <Report instance="ck0001415311-20161231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R23.htm</HtmlFileName>
      <LongName>124 - Statement - Schedule of Investments - Short-Term U.S. Government and Agency Obligations (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.proshares.com/taxonomy/role/StatementScheduleOfInvestmentsShortTermUSGovernmentAndAgencyObligations</Role>
      <ShortName>Schedule of Investments - Short-Term U.S. Government and Agency Obligations (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>23</Position>
    </Report>
    <Report instance="ck0001415311-20161231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R24.htm</HtmlFileName>
      <LongName>125 - Statement - Schedule of Investments - Short-Term U.S. Government and Agency Obligations (Parenthetical) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.proshares.com/taxonomy/role/StatementScheduleOfInvestmentsShortTermUSGovernmentAndAgencyObligationsParenthetical</Role>
      <ShortName>Schedule of Investments - Short-Term U.S. Government and Agency Obligations (Parenthetical) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>24</Position>
    </Report>
    <Report instance="ck0001415311-20161231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R25.htm</HtmlFileName>
      <LongName>126 - Statement - Schedule of Investments - Futures Contracts Purchased (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.proshares.com/taxonomy/role/StatementScheduleOfInvestmentsFuturesContractsPurchased</Role>
      <ShortName>Schedule of Investments - Futures Contracts Purchased (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>25</Position>
    </Report>
    <Report instance="ck0001415311-20161231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R26.htm</HtmlFileName>
      <LongName>127 - Statement - Schedule of Investments - Futures Contracts Purchased (Parenthetical) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.proshares.com/taxonomy/role/StatementScheduleOfInvestmentsFuturesContractsPurchasedParenthetical</Role>
      <ShortName>Schedule of Investments - Futures Contracts Purchased (Parenthetical) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>26</Position>
    </Report>
    <Report instance="ck0001415311-20161231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R27.htm</HtmlFileName>
      <LongName>128 - Statement - Schedule of Investments - Futures Contracts Sold (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.proshares.com/taxonomy/role/StatementScheduleOfInvestmentsFuturesContractsSold</Role>
      <ShortName>Schedule of Investments - Futures Contracts Sold (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>27</Position>
    </Report>
    <Report instance="ck0001415311-20161231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R28.htm</HtmlFileName>
      <LongName>129 - Statement - Schedule of Investments - Futures Contracts Sold (Parenthetical) (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.proshares.com/taxonomy/role/StatementScheduleOfInvestmentsFuturesContractsSoldParenthetical</Role>
      <ShortName>Schedule of Investments - Futures Contracts Sold (Parenthetical) (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>28</Position>
    </Report>
    <Report instance="ck0001415311-20161231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R29.htm</HtmlFileName>
      <LongName>130 - Statement - Schedule of Investments - Swap Agreements (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.proshares.com/taxonomy/role/StatementScheduleOfInvestmentsSwapAgreements</Role>
      <ShortName>Schedule of Investments - Swap Agreements (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>29</Position>
    </Report>
    <Report instance="ck0001415311-20161231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R30.htm</HtmlFileName>
      <LongName>131 - Statement - Schedule of Investments - Forward Agreements (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.proshares.com/taxonomy/role/StatementScheduleOfInvestmentsForwardAgreements</Role>
      <ShortName>Schedule of Investments - Forward Agreements (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>30</Position>
    </Report>
    <Report instance="ck0001415311-20161231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R31.htm</HtmlFileName>
      <LongName>132 - Statement - Schedule of Investments - Foreign Currency Forward Contracts (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.proshares.com/taxonomy/role/StatementScheduleOfInvestmentsForeignCurrencyForwardContracts</Role>
      <ShortName>Schedule of Investments - Foreign Currency Forward Contracts (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>31</Position>
    </Report>
    <Report instance="ck0001415311-20161231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R32.htm</HtmlFileName>
      <LongName>133 - Disclosure - Organization - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.proshares.com/taxonomy/role/DisclosureOrganizationAdditionalInformation</Role>
      <ShortName>Organization - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>32</Position>
    </Report>
    <Report instance="ck0001415311-20161231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R33.htm</HtmlFileName>
      <LongName>134 - Disclosure - Organization - Schedule of Share Splits and Reverse Share Splits (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.proshares.com/taxonomy/role/DisclosureOrganizationScheduleOfShareSplitsAndReverseShareSplits</Role>
      <ShortName>Organization - Schedule of Share Splits and Reverse Share Splits (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>33</Position>
    </Report>
    <Report instance="ck0001415311-20161231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R34.htm</HtmlFileName>
      <LongName>135 - Disclosure - Significant Accounting Policies - Cut-off Times and Times of Calculation of Funds' Final Net Asset Value for Creation and Redemption of Fund Shares (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.proshares.com/taxonomy/role/DisclosureSignificantAccountingPoliciesCutoffTimesAndTimesOfCalculationOfFundsFinalNetAssetValueForCreationAndRedemptionOfFundShares</Role>
      <ShortName>Significant Accounting Policies - Cut-off Times and Times of Calculation of Funds' Final Net Asset Value for Creation and Redemption of Fund Shares (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>34</Position>
    </Report>
    <Report instance="ck0001415311-20161231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R35.htm</HtmlFileName>
      <LongName>136 - Disclosure - Significant Accounting Policies - Valuation of Investments using Fair Value Hierarchy (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.proshares.com/taxonomy/role/DisclosureSignificantAccountingPoliciesValuationOfInvestmentsUsingFairValueHierarchy</Role>
      <ShortName>Significant Accounting Policies - Valuation of Investments using Fair Value Hierarchy (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>35</Position>
    </Report>
    <Report instance="ck0001415311-20161231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R36.htm</HtmlFileName>
      <LongName>137 - Disclosure - Significant Accounting Policies - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.proshares.com/taxonomy/role/DisclosureSignificantAccountingPoliciesAdditionalInformation</Role>
      <ShortName>Significant Accounting Policies - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>36</Position>
    </Report>
    <Report instance="ck0001415311-20161231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R37.htm</HtmlFileName>
      <LongName>138 - Disclosure - Investments - Fair Value of Derivative Instruments (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.proshares.com/taxonomy/role/DisclosureInvestmentsFairValueOfDerivativeInstruments</Role>
      <ShortName>Investments - Fair Value of Derivative Instruments (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>37</Position>
    </Report>
    <Report instance="ck0001415311-20161231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R38.htm</HtmlFileName>
      <LongName>139 - Disclosure - Investments - Effect of Derivative Instruments on Statements of Operations (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.proshares.com/taxonomy/role/DisclosureInvestmentsEffectOfDerivativeInstrumentsOnStatementsOfOperations</Role>
      <ShortName>Investments - Effect of Derivative Instruments on Statements of Operations (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>38</Position>
    </Report>
    <Report instance="ck0001415311-20161231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R39.htm</HtmlFileName>
      <LongName>140 - Disclosure - Investments - Offsetting of Financial Assets and Liabilities (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.proshares.com/taxonomy/role/DisclosureInvestmentsOffsettingOfFinancialAssetsAndLiabilities</Role>
      <ShortName>Investments - Offsetting of Financial Assets and Liabilities (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>39</Position>
    </Report>
    <Report instance="ck0001415311-20161231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R40.htm</HtmlFileName>
      <LongName>141 - Disclosure - Investments - Gross Amounts Not Offset in Statements of Financial Condition (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.proshares.com/taxonomy/role/DisclosureInvestmentsGrossAmountsNotOffsetInStatementsOfFinancialCondition</Role>
      <ShortName>Investments - Gross Amounts Not Offset in Statements of Financial Condition (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>40</Position>
    </Report>
    <Report instance="ck0001415311-20161231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R41.htm</HtmlFileName>
      <LongName>142 - Disclosure - Agreements - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.proshares.com/taxonomy/role/DisclosureAgreementsAdditionalInformation</Role>
      <ShortName>Agreements - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>41</Position>
    </Report>
    <Report instance="ck0001415311-20161231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R42.htm</HtmlFileName>
      <LongName>143 - Disclosure - Offering Costs - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.proshares.com/taxonomy/role/DisclosureOfferingCostsAdditionalInformation</Role>
      <ShortName>Offering Costs - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>42</Position>
    </Report>
    <Report instance="ck0001415311-20161231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R43.htm</HtmlFileName>
      <LongName>144 - Disclosure - Creation and Redemption of Creation Units - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.proshares.com/taxonomy/role/DisclosureCreationAndRedemptionOfCreationUnitsAdditionalInformation</Role>
      <ShortName>Creation and Redemption of Creation Units - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>43</Position>
    </Report>
    <Report instance="ck0001415311-20161231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R44.htm</HtmlFileName>
      <LongName>145 - Disclosure - Creation and Redemption of Creation Units - Schedule of Transaction Fees (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.proshares.com/taxonomy/role/DisclosureCreationAndRedemptionOfCreationUnitsScheduleOfTransactionFees</Role>
      <ShortName>Creation and Redemption of Creation Units - Schedule of Transaction Fees (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>44</Position>
    </Report>
    <Report instance="ck0001415311-20161231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R45.htm</HtmlFileName>
      <LongName>146 - Disclosure - Financial Highlights - Per Share Operating Performance (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.proshares.com/taxonomy/role/DisclosureFinancialHighlightsPerShareOperatingPerformance</Role>
      <ShortName>Financial Highlights - Per Share Operating Performance (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>45</Position>
    </Report>
    <Report instance="ck0001415311-20161231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R46.htm</HtmlFileName>
      <LongName>147 - Disclosure - Risk - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.proshares.com/taxonomy/role/DisclosureRiskAdditionalInformation</Role>
      <ShortName>Risk - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>46</Position>
    </Report>
    <Report instance="ck0001415311-20161231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R47.htm</HtmlFileName>
      <LongName>148 - Disclosure - Subsequent Events - Additional Information (Detail)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.proshares.com/taxonomy/role/DisclosureSubsequentEventsAdditionalInformation</Role>
      <ShortName>Subsequent Events - Additional Information (Detail)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>47</Position>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <LongName>All Reports</LongName>
      <ReportType>Book</ReportType>
      <ShortName>All Reports</ShortName>
    </Report>
  </MyReports>
  <InputFiles>
    <File>ck0001415311-20161231.xml</File>
    <File>ck0001415311-20161231.xsd</File>
    <File>ck0001415311-20161231_cal.xml</File>
    <File>ck0001415311-20161231_def.xml</File>
    <File>ck0001415311-20161231_lab.xml</File>
    <File>ck0001415311-20161231_pre.xml</File>
  </InputFiles>
  <SupplementalFiles/>
  <BaseTaxonomies/>
  <HasPresentationLinkbase>true</HasPresentationLinkbase>
  <HasCalculationLinkbase>true</HasCalculationLinkbase>
</FilingSummary>
