<?xml version='1.0' encoding='UTF-8'?>
<FilingSummary>
  <Version>3.8.0.1</Version>
  <ProcessingTime/>
  <ReportFormat>html</ReportFormat>
  <ContextCount>191</ContextCount>
  <ElementCount>279</ElementCount>
  <EntityCount>1</EntityCount>
  <FootnotesReported>false</FootnotesReported>
  <SegmentCount>45</SegmentCount>
  <ScenarioCount>0</ScenarioCount>
  <TuplesReported>false</TuplesReported>
  <UnitCount>4</UnitCount>
  <MyReports>
    <Report instance="atxi-20171231.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.avenuetx.com/role/DocumentAndEntityInformation</Role>
      <ShortName>Document And Entity Information</ShortName>
      <MenuCategory>Cover</MenuCategory>
      <Position>1</Position>
    </Report>
    <Report instance="atxi-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R2.htm</HtmlFileName>
      <LongName>102 - Statement - BALANCE SHEETS</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avenuetx.com/role/BalanceSheets</Role>
      <ShortName>BALANCE SHEETS</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>2</Position>
    </Report>
    <Report instance="atxi-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R3.htm</HtmlFileName>
      <LongName>103 - Statement - BALANCE SHEETS (Parenthetical)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avenuetx.com/role/BalanceSheetsParenthetical</Role>
      <ShortName>BALANCE SHEETS (Parenthetical)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>3</Position>
    </Report>
    <Report instance="atxi-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R4.htm</HtmlFileName>
      <LongName>104 - Statement - STATEMENTS OF OPERATIONS</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avenuetx.com/role/StatementsOfOperations</Role>
      <ShortName>STATEMENTS OF OPERATIONS</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>4</Position>
    </Report>
    <Report instance="atxi-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R5.htm</HtmlFileName>
      <LongName>105 - Statement - STATEMENTS OF STOCKHOLDERS' EQUITY (DEFICIT)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avenuetx.com/role/StatementsOfStockholdersEquityDeficit</Role>
      <ShortName>STATEMENTS OF STOCKHOLDERS' EQUITY (DEFICIT)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>5</Position>
    </Report>
    <Report instance="atxi-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R6.htm</HtmlFileName>
      <LongName>106 - Statement - STATEMENTS OF CASH FLOWS</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avenuetx.com/role/StatementsOfCashFlows</Role>
      <ShortName>STATEMENTS OF CASH FLOWS</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>6</Position>
    </Report>
    <Report instance="atxi-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R7.htm</HtmlFileName>
      <LongName>107 - Disclosure - Organization, Plan of Business Operations</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avenuetx.com/role/OrganizationPlanOfBusinessOperations</Role>
      <ShortName>Organization, Plan of Business Operations</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>7</Position>
    </Report>
    <Report instance="atxi-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R8.htm</HtmlFileName>
      <LongName>108 - Disclosure - Significant Accounting Policies</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avenuetx.com/role/SignificantAccountingPolicies</Role>
      <ShortName>Significant Accounting Policies</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>8</Position>
    </Report>
    <Report instance="atxi-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R9.htm</HtmlFileName>
      <LongName>109 - Disclosure - Allocation</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avenuetx.com/role/Allocation</Role>
      <ShortName>Allocation</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>9</Position>
    </Report>
    <Report instance="atxi-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R10.htm</HtmlFileName>
      <LongName>110 - Disclosure - License Agreement</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avenuetx.com/role/LicenseAgreement</Role>
      <ShortName>License Agreement</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>10</Position>
    </Report>
    <Report instance="atxi-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R11.htm</HtmlFileName>
      <LongName>111 - Disclosure - Related Party Agreements</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avenuetx.com/role/RelatedPartyAgreements</Role>
      <ShortName>Related Party Agreements</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>11</Position>
    </Report>
    <Report instance="atxi-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R12.htm</HtmlFileName>
      <LongName>112 - Disclosure - Accounts Payable and Accrued Expenses</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avenuetx.com/role/AccountsPayableAndAccruedExpenses</Role>
      <ShortName>Accounts Payable and Accrued Expenses</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>12</Position>
    </Report>
    <Report instance="atxi-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R13.htm</HtmlFileName>
      <LongName>113 - Disclosure - Notes Payable</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://www.avenuetx.com/role/NotesPayable</Role>
      <ShortName>Notes Payable</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>13</Position>
    </Report>
    <Report instance="atxi-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R14.htm</HtmlFileName>
      <LongName>114 - Disclosure - Commitments and Contingencies</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avenuetx.com/role/CommitmentsAndContingencies</Role>
      <ShortName>Commitments and Contingencies</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>14</Position>
    </Report>
    <Report instance="atxi-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R15.htm</HtmlFileName>
      <LongName>115 - Disclosure - Stockholders??? Equity (Deficit)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avenuetx.com/role/StockholdersEquityDeficit</Role>
      <ShortName>Stockholders??? Equity (Deficit)</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>15</Position>
    </Report>
    <Report instance="atxi-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R16.htm</HtmlFileName>
      <LongName>116 - Disclosure - Fair Value Measurement</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avenuetx.com/role/FairValueMeasurement</Role>
      <ShortName>Fair Value Measurement</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>16</Position>
    </Report>
    <Report instance="atxi-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R17.htm</HtmlFileName>
      <LongName>117 - Disclosure - Income Taxes</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avenuetx.com/role/IncomeTaxes</Role>
      <ShortName>Income Taxes</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>17</Position>
    </Report>
    <Report instance="atxi-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R18.htm</HtmlFileName>
      <LongName>118 - Disclosure - Quarterly Financial Data (unaudited)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avenuetx.com/role/QuarterlyFinancialDataUnaudited</Role>
      <ShortName>Quarterly Financial Data (unaudited)</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>18</Position>
    </Report>
    <Report instance="atxi-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R19.htm</HtmlFileName>
      <LongName>119 - Disclosure - Significant Accounting Policies (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avenuetx.com/role/SignificantAccountingPoliciesPolicies</Role>
      <ShortName>Significant Accounting Policies (Policies)</ShortName>
      <MenuCategory>Policies</MenuCategory>
      <ParentRole>http://www.avenuetx.com/role/SignificantAccountingPolicies</ParentRole>
      <Position>19</Position>
    </Report>
    <Report instance="atxi-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R20.htm</HtmlFileName>
      <LongName>120 - Disclosure - Significant Accounting Policies (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avenuetx.com/role/SignificantAccountingPoliciesTables</Role>
      <ShortName>Significant Accounting Policies (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.avenuetx.com/role/SignificantAccountingPolicies</ParentRole>
      <Position>20</Position>
    </Report>
    <Report instance="atxi-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R21.htm</HtmlFileName>
      <LongName>121 - Disclosure - Accounts Payable and Accrued Expenses (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avenuetx.com/role/AccountsPayableAndAccruedExpensesTables</Role>
      <ShortName>Accounts Payable and Accrued Expenses (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.avenuetx.com/role/AccountsPayableAndAccruedExpenses</ParentRole>
      <Position>21</Position>
    </Report>
    <Report instance="atxi-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R22.htm</HtmlFileName>
      <LongName>122 - Disclosure - Notes Payable (Tables)</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://www.avenuetx.com/role/NotesPayableTables</Role>
      <ShortName>Notes Payable (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.avenuetx.com/role/NotesPayable</ParentRole>
      <Position>22</Position>
    </Report>
    <Report instance="atxi-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R23.htm</HtmlFileName>
      <LongName>123 - Disclosure - Stockholders??? Equity (Deficit) (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avenuetx.com/role/StockholdersEquityDeficitTables</Role>
      <ShortName>Stockholders??? Equity (Deficit) (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.avenuetx.com/role/StockholdersEquityDeficit</ParentRole>
      <Position>23</Position>
    </Report>
    <Report instance="atxi-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R24.htm</HtmlFileName>
      <LongName>124 - Disclosure - Fair Value Measurement (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avenuetx.com/role/FairValueMeasurementTables</Role>
      <ShortName>Fair Value Measurement (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.avenuetx.com/role/FairValueMeasurement</ParentRole>
      <Position>24</Position>
    </Report>
    <Report instance="atxi-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R25.htm</HtmlFileName>
      <LongName>125 - Disclosure - Income Taxes (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avenuetx.com/role/IncomeTaxesTables</Role>
      <ShortName>Income Taxes (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.avenuetx.com/role/IncomeTaxes</ParentRole>
      <Position>25</Position>
    </Report>
    <Report instance="atxi-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R26.htm</HtmlFileName>
      <LongName>126 - Disclosure - Quarterly Financial Data (unaudited) (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avenuetx.com/role/QuarterlyFinancialDataUnauditedTables</Role>
      <ShortName>Quarterly Financial Data (unaudited) (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.avenuetx.com/role/QuarterlyFinancialDataUnaudited</ParentRole>
      <Position>26</Position>
    </Report>
    <Report instance="atxi-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R27.htm</HtmlFileName>
      <LongName>127 - Disclosure - Organization, Plan of Business Operations (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avenuetx.com/role/OrganizationPlanOfBusinessOperationsDetailsTextual</Role>
      <ShortName>Organization, Plan of Business Operations (Details Textual)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.avenuetx.com/role/OrganizationPlanOfBusinessOperations</ParentRole>
      <Position>27</Position>
    </Report>
    <Report instance="atxi-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R28.htm</HtmlFileName>
      <LongName>128 - Disclosure - Significant Accounting Policies (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avenuetx.com/role/SignificantAccountingPoliciesDetails</Role>
      <ShortName>Significant Accounting Policies (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.avenuetx.com/role/SignificantAccountingPoliciesTables</ParentRole>
      <Position>28</Position>
    </Report>
    <Report instance="atxi-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R29.htm</HtmlFileName>
      <LongName>129 - Disclosure - Significant Accounting Policies (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avenuetx.com/role/SignificantAccountingPoliciesDetailsTextual</Role>
      <ShortName>Significant Accounting Policies (Details Textual)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.avenuetx.com/role/SignificantAccountingPoliciesTables</ParentRole>
      <Position>29</Position>
    </Report>
    <Report instance="atxi-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R30.htm</HtmlFileName>
      <LongName>130 - Disclosure - Allocation (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avenuetx.com/role/AllocationDetailsTextual</Role>
      <ShortName>Allocation (Details Textual)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.avenuetx.com/role/Allocation</ParentRole>
      <Position>30</Position>
    </Report>
    <Report instance="atxi-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R31.htm</HtmlFileName>
      <LongName>131 - Disclosure - License Agreement (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avenuetx.com/role/LicenseAgreementDetailsTextual</Role>
      <ShortName>License Agreement (Details Textual)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.avenuetx.com/role/LicenseAgreement</ParentRole>
      <Position>31</Position>
    </Report>
    <Report instance="atxi-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R32.htm</HtmlFileName>
      <LongName>132 - Disclosure - Related Party Agreements (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avenuetx.com/role/RelatedPartyAgreementsDetailsTextual</Role>
      <ShortName>Related Party Agreements (Details Textual)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.avenuetx.com/role/RelatedPartyAgreements</ParentRole>
      <Position>32</Position>
    </Report>
    <Report instance="atxi-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R33.htm</HtmlFileName>
      <LongName>133 - Disclosure - Accounts Payable and Accrued Expenses (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avenuetx.com/role/AccountsPayableAndAccruedExpensesDetails</Role>
      <ShortName>Accounts Payable and Accrued Expenses (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.avenuetx.com/role/AccountsPayableAndAccruedExpensesTables</ParentRole>
      <Position>33</Position>
    </Report>
    <Report instance="atxi-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R34.htm</HtmlFileName>
      <LongName>134 - Disclosure - Notes Payable (Details)</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://www.avenuetx.com/role/NotesPayableDetails</Role>
      <ShortName>Notes Payable (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.avenuetx.com/role/NotesPayableTables</ParentRole>
      <Position>34</Position>
    </Report>
    <Report instance="atxi-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R35.htm</HtmlFileName>
      <LongName>135 - Disclosure - Notes Payable (Details Textual)</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://www.avenuetx.com/role/NotesPayableDetailsTextual</Role>
      <ShortName>Notes Payable (Details Textual)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.avenuetx.com/role/NotesPayableTables</ParentRole>
      <Position>35</Position>
    </Report>
    <Report instance="atxi-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R36.htm</HtmlFileName>
      <LongName>136 - Disclosure - Stockholders??? Equity (Deficit) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avenuetx.com/role/StockholdersEquityDeficitDetails</Role>
      <ShortName>Stockholders??? Equity (Deficit) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.avenuetx.com/role/StockholdersEquityDeficitTables</ParentRole>
      <Position>36</Position>
    </Report>
    <Report instance="atxi-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R37.htm</HtmlFileName>
      <LongName>137 - Disclosure - Stockholders??? Equity (Deficit) (Details1)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avenuetx.com/role/StockholdersEquityDeficitDetails1</Role>
      <ShortName>Stockholders??? Equity (Deficit) (Details1)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.avenuetx.com/role/StockholdersEquityDeficitTables</ParentRole>
      <Position>37</Position>
    </Report>
    <Report instance="atxi-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R38.htm</HtmlFileName>
      <LongName>138 - Disclosure - Stockholders??? Equity (Deficit) (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avenuetx.com/role/StockholdersEquityDeficitDetailsTextual</Role>
      <ShortName>Stockholders??? Equity (Deficit) (Details Textual)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.avenuetx.com/role/StockholdersEquityDeficitTables</ParentRole>
      <Position>38</Position>
    </Report>
    <Report instance="atxi-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R39.htm</HtmlFileName>
      <LongName>139 - Disclosure - Fair Value Measurement (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avenuetx.com/role/FairValueMeasurementDetails</Role>
      <ShortName>Fair Value Measurement (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.avenuetx.com/role/FairValueMeasurementTables</ParentRole>
      <Position>39</Position>
    </Report>
    <Report instance="atxi-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R40.htm</HtmlFileName>
      <LongName>140 - Disclosure - Fair Value Measurement (Details 1)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avenuetx.com/role/FairValueMeasurementDetails1</Role>
      <ShortName>Fair Value Measurement (Details 1)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.avenuetx.com/role/FairValueMeasurementTables</ParentRole>
      <Position>40</Position>
    </Report>
    <Report instance="atxi-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R41.htm</HtmlFileName>
      <LongName>141 - Disclosure - Fair Value Measurement (Details 2)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avenuetx.com/role/FairValueMeasurementDetails2</Role>
      <ShortName>Fair Value Measurement (Details 2)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.avenuetx.com/role/FairValueMeasurementTables</ParentRole>
      <Position>41</Position>
    </Report>
    <Report instance="atxi-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R42.htm</HtmlFileName>
      <LongName>142 - Disclosure - Fair Value Measurement (Details 3)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avenuetx.com/role/FairValueMeasurementDetails3</Role>
      <ShortName>Fair Value Measurement (Details 3)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.avenuetx.com/role/FairValueMeasurementTables</ParentRole>
      <Position>42</Position>
    </Report>
    <Report instance="atxi-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R43.htm</HtmlFileName>
      <LongName>143 - Disclosure - Fair Value Measurement (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avenuetx.com/role/FairValueMeasurementDetailsTextual</Role>
      <ShortName>Fair Value Measurement (Details Textual)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.avenuetx.com/role/FairValueMeasurementTables</ParentRole>
      <Position>43</Position>
    </Report>
    <Report instance="atxi-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R44.htm</HtmlFileName>
      <LongName>144 - Disclosure - Income Taxes (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avenuetx.com/role/IncomeTaxesDetails</Role>
      <ShortName>Income Taxes (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.avenuetx.com/role/IncomeTaxesTables</ParentRole>
      <Position>44</Position>
    </Report>
    <Report instance="atxi-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R45.htm</HtmlFileName>
      <LongName>145 - Disclosure - Income Taxes (Details 1)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avenuetx.com/role/IncomeTaxesDetails1</Role>
      <ShortName>Income Taxes (Details 1)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.avenuetx.com/role/IncomeTaxesTables</ParentRole>
      <Position>45</Position>
    </Report>
    <Report instance="atxi-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R46.htm</HtmlFileName>
      <LongName>146 - Disclosure - Income Taxes (Details Textual)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avenuetx.com/role/IncomeTaxesDetailsTextual</Role>
      <ShortName>Income Taxes (Details Textual)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.avenuetx.com/role/IncomeTaxesTables</ParentRole>
      <Position>46</Position>
    </Report>
    <Report instance="atxi-20171231.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R47.htm</HtmlFileName>
      <LongName>147 - Disclosure - Quarterly Financial Data (unaudited) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avenuetx.com/role/QuarterlyFinancialDataUnauditedDetails</Role>
      <ShortName>Quarterly Financial Data (unaudited) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.avenuetx.com/role/QuarterlyFinancialDataUnauditedTables</ParentRole>
      <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>atxi-20171231.xml</File>
    <File>atxi-20171231.xsd</File>
    <File>atxi-20171231_cal.xml</File>
    <File>atxi-20171231_def.xml</File>
    <File>atxi-20171231_lab.xml</File>
    <File>atxi-20171231_pre.xml</File>
  </InputFiles>
  <SupplementalFiles/>
  <BaseTaxonomies>
    <BaseTaxonomy>http://fasb.org/us-gaap/2017-01-31</BaseTaxonomy>
    <BaseTaxonomy>http://xbrl.sec.gov/dei/2014-01-31</BaseTaxonomy>
  </BaseTaxonomies>
  <HasPresentationLinkbase>true</HasPresentationLinkbase>
  <HasCalculationLinkbase>true</HasCalculationLinkbase>
</FilingSummary>
