<?xml version='1.0' encoding='UTF-8'?>
<FilingSummary>
  <Version>3.3.0.814</Version>
  <ProcessingTime/>
  <ReportFormat>html</ReportFormat>
  <ContextCount>942</ContextCount>
  <ElementCount>568</ElementCount>
  <EntityCount>1</EntityCount>
  <FootnotesReported>true</FootnotesReported>
  <SegmentCount>232</SegmentCount>
  <ScenarioCount>0</ScenarioCount>
  <TuplesReported>false</TuplesReported>
  <UnitCount>10</UnitCount>
  <MyReports>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R1.htm</HtmlFileName>
      <LongName>0001000 - Document - Document And Entity Information</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/DocumentAndEntityInformation</Role>
      <ShortName>Document And Entity Information</ShortName>
      <MenuCategory>Cover</MenuCategory>
      <Position>1</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R2.htm</HtmlFileName>
      <LongName>1001000 - Statement - Consolidated Statements Of Operations</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/ConsolidatedStatementsOfOperations</Role>
      <ShortName>Consolidated Statements Of Operations</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>2</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R3.htm</HtmlFileName>
      <LongName>1002000 - Statement - Consolidated Statements of Comprehensive Loss Statement</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/ConsolidatedStatementsOfComprehensiveLossStatement</Role>
      <ShortName>Consolidated Statements of Comprehensive Loss Statement</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>3</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R4.htm</HtmlFileName>
      <LongName>1002001 - Statement - Consolidated Statements of Comprehensive Loss (Parenthetical)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/ConsolidatedStatementsOfComprehensiveLossParenthetical</Role>
      <ShortName>Consolidated Statements of Comprehensive Loss (Parenthetical)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>4</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R5.htm</HtmlFileName>
      <LongName>1003000 - Statement - Consolidated Balance Sheets</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/ConsolidatedBalanceSheets</Role>
      <ShortName>Consolidated Balance Sheets</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>5</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R6.htm</HtmlFileName>
      <LongName>1003501 - Statement - Consolidated Balance Sheets (Parenthetical)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/ConsolidatedBalanceSheetsParenthetical</Role>
      <ShortName>Consolidated Balance Sheets (Parenthetical)</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>6</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R7.htm</HtmlFileName>
      <LongName>1005000 - Statement - Consolidated Statements of Changes in Stockholder's Deficiency</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/ConsolidatedStatementsOfChangesInStockholdersDeficiency</Role>
      <ShortName>Consolidated Statements of Changes in Stockholder's Deficiency</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>7</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R8.htm</HtmlFileName>
      <LongName>1006000 - Statement - Consolidated Statements Of Cash Flows</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/ConsolidatedStatementsOfCashFlows</Role>
      <ShortName>Consolidated Statements Of Cash Flows</ShortName>
      <MenuCategory>Statements</MenuCategory>
      <Position>8</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R9.htm</HtmlFileName>
      <LongName>2101100 - Disclosure - Background and Basis of Presentation</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/BackgroundAndBasisOfPresentation</Role>
      <ShortName>Background and Basis of Presentation</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>9</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R10.htm</HtmlFileName>
      <LongName>2102100 - Disclosure - Summary of Significant Accounting Policies</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/SummaryOfSignificantAccountingPolicies</Role>
      <ShortName>Summary of Significant Accounting Policies</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>10</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R11.htm</HtmlFileName>
      <LongName>2103100 - Disclosure - Recent Accounting Pronouncements</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/RecentAccountingPronouncements</Role>
      <ShortName>Recent Accounting Pronouncements</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>11</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R12.htm</HtmlFileName>
      <LongName>2104100 - Disclosure - Business Combinations and Other Transactions</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/BusinessCombinationsAndOtherTransactions</Role>
      <ShortName>Business Combinations and Other Transactions</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>12</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R13.htm</HtmlFileName>
      <LongName>2105100 - Disclosure - Divestitures</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/Divestitures</Role>
      <ShortName>Divestitures</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>13</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R14.htm</HtmlFileName>
      <LongName>2106100 - Disclosure - Goodwill</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/Goodwill</Role>
      <ShortName>Goodwill</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>14</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R15.htm</HtmlFileName>
      <LongName>2107100 - Disclosure - Acquired Intangible Assets</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/AcquiredIntangibleAssets</Role>
      <ShortName>Acquired Intangible Assets</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>15</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R16.htm</HtmlFileName>
      <LongName>2108100 - Disclosure - Supplementary Financial Information</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/SupplementaryFinancialInformation</Role>
      <ShortName>Supplementary Financial Information</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>16</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R17.htm</HtmlFileName>
      <LongName>2109100 - Disclosure - Business Restructuring Reserves And Programs</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/BusinessRestructuringReservesAndPrograms</Role>
      <ShortName>Business Restructuring Reserves And Programs</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>17</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R18.htm</HtmlFileName>
      <LongName>2110100 - Disclosure - Financing Arrangements</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/FinancingArrangements</Role>
      <ShortName>Financing Arrangements</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>18</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R19.htm</HtmlFileName>
      <LongName>2111100 - Disclosure - Derivatives And Other Financial Instruments</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/DerivativesAndOtherFinancialInstruments</Role>
      <ShortName>Derivatives And Other Financial Instruments</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>19</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R20.htm</HtmlFileName>
      <LongName>2112100 - Disclosure - Fair Value Measures</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/FairValueMeasures</Role>
      <ShortName>Fair Value Measures</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>20</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R21.htm</HtmlFileName>
      <LongName>2113100 - Disclosure - Income Taxes</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/IncomeTaxes</Role>
      <ShortName>Income Taxes</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>21</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R22.htm</HtmlFileName>
      <LongName>2114100 - Disclosure - Benefit Obligations</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/BenefitObligations</Role>
      <ShortName>Benefit Obligations</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>22</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R23.htm</HtmlFileName>
      <LongName>2115100 - Disclosure - Share-Based Compensation</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/ShareBasedCompensation</Role>
      <ShortName>Share-Based Compensation</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>23</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R24.htm</HtmlFileName>
      <LongName>2116100 - Disclosure - Reportable Segments</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/ReportableSegments</Role>
      <ShortName>Reportable Segments</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>24</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R25.htm</HtmlFileName>
      <LongName>2117100 - Disclosure - Accumulated Other Comprehensive Loss (Notes)</LongName>
      <ReportType>Notes</ReportType>
      <Role>http://www.avaya.com/role/AccumulatedOtherComprehensiveLossNotes</Role>
      <ShortName>Accumulated Other Comprehensive Loss (Notes)</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>25</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R26.htm</HtmlFileName>
      <LongName>2118100 - Disclosure - Related Party Transactions</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/RelatedPartyTransactions</Role>
      <ShortName>Related Party Transactions</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>26</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R27.htm</HtmlFileName>
      <LongName>2119100 - Disclosure - Commitments And Contingencies</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/CommitmentsAndContingencies</Role>
      <ShortName>Commitments And Contingencies</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>27</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R28.htm</HtmlFileName>
      <LongName>2120100 - Disclosure - Quarterly Information (unaudited)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/QuarterlyInformationUnaudited</Role>
      <ShortName>Quarterly Information (unaudited)</ShortName>
      <MenuCategory>Notes</MenuCategory>
      <Position>28</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R29.htm</HtmlFileName>
      <LongName>2202201 - Disclosure - Summary of Significant Accounting Policies (Policies)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/SummaryOfSignificantAccountingPoliciesPolicies</Role>
      <ShortName>Summary of Significant Accounting Policies (Policies)</ShortName>
      <MenuCategory>Policies</MenuCategory>
      <ParentRole>http://www.avaya.com/role/SummaryOfSignificantAccountingPolicies</ParentRole>
      <Position>29</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R30.htm</HtmlFileName>
      <LongName>2305301 - Disclosure - Divestitures (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/DivestituresTables</Role>
      <ShortName>Divestitures (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.avaya.com/role/Divestitures</ParentRole>
      <Position>30</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R31.htm</HtmlFileName>
      <LongName>2306301 - Disclosure - Goodwill (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/GoodwillTables</Role>
      <ShortName>Goodwill (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.avaya.com/role/Goodwill</ParentRole>
      <Position>31</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R32.htm</HtmlFileName>
      <LongName>2307301 - Disclosure - Acquired Intangible Assets (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/AcquiredIntangibleAssetsTables</Role>
      <ShortName>Acquired Intangible Assets (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.avaya.com/role/AcquiredIntangibleAssets</ParentRole>
      <Position>32</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R33.htm</HtmlFileName>
      <LongName>2308301 - Disclosure - Supplementary Financial Information (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/SupplementaryFinancialInformationTables</Role>
      <ShortName>Supplementary Financial Information (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.avaya.com/role/SupplementaryFinancialInformation</ParentRole>
      <Position>33</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R34.htm</HtmlFileName>
      <LongName>2309301 - Disclosure - Business Restructuring Reserves And Programs (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/BusinessRestructuringReservesAndProgramsTables</Role>
      <ShortName>Business Restructuring Reserves And Programs (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.avaya.com/role/BusinessRestructuringReservesAndPrograms</ParentRole>
      <Position>34</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R35.htm</HtmlFileName>
      <LongName>2310301 - Disclosure - Financing Arrangements (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/FinancingArrangementsTables</Role>
      <ShortName>Financing Arrangements (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.avaya.com/role/FinancingArrangements</ParentRole>
      <Position>35</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R36.htm</HtmlFileName>
      <LongName>2311301 - Disclosure - Derivatives And Other Financial Instruments (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/DerivativesAndOtherFinancialInstrumentsTables</Role>
      <ShortName>Derivatives And Other Financial Instruments (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.avaya.com/role/DerivativesAndOtherFinancialInstruments</ParentRole>
      <Position>36</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R37.htm</HtmlFileName>
      <LongName>2312301 - Disclosure - Fair Value Measures (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/FairValueMeasuresTables</Role>
      <ShortName>Fair Value Measures (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.avaya.com/role/FairValueMeasures</ParentRole>
      <Position>37</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R38.htm</HtmlFileName>
      <LongName>2313301 - Disclosure - Income Taxes (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/IncomeTaxesTables</Role>
      <ShortName>Income Taxes (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.avaya.com/role/IncomeTaxes</ParentRole>
      <Position>38</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R39.htm</HtmlFileName>
      <LongName>2314301 - Disclosure - Benefit Obligations (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/BenefitObligationsTables</Role>
      <ShortName>Benefit Obligations (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.avaya.com/role/BenefitObligations</ParentRole>
      <Position>39</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R40.htm</HtmlFileName>
      <LongName>2315301 - Disclosure - Share-Based Compensation (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/ShareBasedCompensationTables</Role>
      <ShortName>Share-Based Compensation (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.avaya.com/role/ShareBasedCompensation</ParentRole>
      <Position>40</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R41.htm</HtmlFileName>
      <LongName>2316301 - Disclosure - Reportable Segments (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/ReportableSegmentsTables</Role>
      <ShortName>Reportable Segments (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.avaya.com/role/ReportableSegments</ParentRole>
      <Position>41</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R42.htm</HtmlFileName>
      <LongName>2317301 - Disclosure - Accumulated Other Comprehensive Loss (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/AccumulatedOtherComprehensiveLossTables</Role>
      <ShortName>Accumulated Other Comprehensive Loss (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.avaya.com/role/AccumulatedOtherComprehensiveLossNotes</ParentRole>
      <Position>42</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R43.htm</HtmlFileName>
      <LongName>2319301 - Disclosure - Commitments And Contingencies (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/CommitmentsAndContingenciesTables</Role>
      <ShortName>Commitments And Contingencies (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.avaya.com/role/CommitmentsAndContingencies</ParentRole>
      <Position>43</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R44.htm</HtmlFileName>
      <LongName>2320301 - Disclosure - Quarterly Information (unaudited) (Tables)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/QuarterlyInformationUnauditedTables</Role>
      <ShortName>Quarterly Information (unaudited) (Tables)</ShortName>
      <MenuCategory>Tables</MenuCategory>
      <ParentRole>http://www.avaya.com/role/QuarterlyInformationUnaudited</ParentRole>
      <Position>44</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R45.htm</HtmlFileName>
      <LongName>2401401 - Disclosure - Background and Basis of Presentation (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/BackgroundAndBasisOfPresentationDetails</Role>
      <ShortName>Background and Basis of Presentation (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.avaya.com/role/BackgroundAndBasisOfPresentation</ParentRole>
      <Position>45</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R46.htm</HtmlFileName>
      <LongName>2402402 - Disclosure - Summary of Significant Accounting Policies (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/SummaryOfSignificantAccountingPoliciesDetails</Role>
      <ShortName>Summary of Significant Accounting Policies (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.avaya.com/role/SummaryOfSignificantAccountingPoliciesPolicies</ParentRole>
      <Position>46</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R47.htm</HtmlFileName>
      <LongName>2404401 - Disclosure - Business Combinations and Other Transactions (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/BusinessCombinationsAndOtherTransactionsDetails</Role>
      <ShortName>Business Combinations and Other Transactions (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.avaya.com/role/BusinessCombinationsAndOtherTransactions</ParentRole>
      <Position>47</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R48.htm</HtmlFileName>
      <LongName>2405402 - Disclosure - Divestitures (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/DivestituresDetails</Role>
      <ShortName>Divestitures (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.avaya.com/role/DivestituresTables</ParentRole>
      <Position>48</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R49.htm</HtmlFileName>
      <LongName>2406402 - Disclosure - Goodwill (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/GoodwillDetails</Role>
      <ShortName>Goodwill (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.avaya.com/role/GoodwillTables</ParentRole>
      <Position>49</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R50.htm</HtmlFileName>
      <LongName>2407402 - Disclosure - Acquired Intangible Assets (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/AcquiredIntangibleAssetsDetails</Role>
      <ShortName>Acquired Intangible Assets (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.avaya.com/role/AcquiredIntangibleAssetsTables</ParentRole>
      <Position>50</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R51.htm</HtmlFileName>
      <LongName>2407403 - Disclosure - Acquired Intangible Assets Amortization Expense Maturity (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/AcquiredIntangibleAssetsAmortizationExpenseMaturityDetails</Role>
      <ShortName>Acquired Intangible Assets Amortization Expense Maturity (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>51</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R52.htm</HtmlFileName>
      <LongName>2408402 - Disclosure - Supplementary Financial Information - Consolidated Statements of Operations Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/SupplementaryFinancialInformationConsolidatedStatementsOfOperationsInformationDetails</Role>
      <ShortName>Supplementary Financial Information - Consolidated Statements of Operations Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>52</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R53.htm</HtmlFileName>
      <LongName>2408403 - Disclosure - Supplementary Financial Information - Consolidated Balance Sheet Information Valuation and Qualifying Accounts (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/SupplementaryFinancialInformationConsolidatedBalanceSheetInformationValuationAndQualifyingAccountsDetails</Role>
      <ShortName>Supplementary Financial Information - Consolidated Balance Sheet Information Valuation and Qualifying Accounts (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>53</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R54.htm</HtmlFileName>
      <LongName>2408404 - Disclosure - Supplementary Financial Information - Consolidated Balance Sheet Information Property, Plant and Equipment, Net (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/SupplementaryFinancialInformationConsolidatedBalanceSheetInformationPropertyPlantAndEquipmentNetDetails</Role>
      <ShortName>Supplementary Financial Information - Consolidated Balance Sheet Information Property, Plant and Equipment, Net (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>54</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R55.htm</HtmlFileName>
      <LongName>2408405 - Disclosure - Supplementary Financial Information - Supplementary Cash Flow Information (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/SupplementaryFinancialInformationSupplementaryCashFlowInformationDetails</Role>
      <ShortName>Supplementary Financial Information - Supplementary Cash Flow Information (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>55</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R56.htm</HtmlFileName>
      <LongName>2409402 - Disclosure - Business Restructuring Reserves And Programs (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/BusinessRestructuringReservesAndProgramsDetails</Role>
      <ShortName>Business Restructuring Reserves And Programs (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.avaya.com/role/BusinessRestructuringReservesAndProgramsTables</ParentRole>
      <Position>56</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R57.htm</HtmlFileName>
      <LongName>2410402 - Disclosure - Financing Arrangements - Schedule of long term debt (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/FinancingArrangementsScheduleOfLongTermDebtDetails</Role>
      <ShortName>Financing Arrangements - Schedule of long term debt (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>57</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R58.htm</HtmlFileName>
      <LongName>2410403 - Disclosure - Financing Arrangements - Maturity profile (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/FinancingArrangementsMaturityProfileDetails</Role>
      <ShortName>Financing Arrangements - Maturity profile (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>58</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R59.htm</HtmlFileName>
      <LongName>2410404 - Disclosure - Financing Arrangements - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/FinancingArrangementsNarrativeDetails</Role>
      <ShortName>Financing Arrangements - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>59</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R60.htm</HtmlFileName>
      <LongName>2411402 - Disclosure - Derivatives And Other Financial Instruments - Gains &amp; Losses on Interest Rate Contracts Qualifying and Designated as Cash Flow Hedging Instruments (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/DerivativesAndOtherFinancialInstrumentsGainsLossesOnInterestRateContractsQualifyingAndDesignatedAsCashFlowHedgingInstrumentsDetails</Role>
      <ShortName>Derivatives And Other Financial Instruments - Gains &amp; Losses on Interest Rate Contracts Qualifying and Designated as Cash Flow Hedging Instruments (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>60</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R61.htm</HtmlFileName>
      <LongName>2411403 - Disclosure - Derivatives And Other Financial Instruments - Notional Amounts of Foreign Currency Financial Instruments (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/DerivativesAndOtherFinancialInstrumentsNotionalAmountsOfForeignCurrencyFinancialInstrumentsDetails</Role>
      <ShortName>Derivatives And Other Financial Instruments - Notional Amounts of Foreign Currency Financial Instruments (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>61</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R62.htm</HtmlFileName>
      <LongName>2411405 - Disclosure - Derivatives And Other Financial Instruments - Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/DerivativesAndOtherFinancialInstrumentsNarrativeDetails</Role>
      <ShortName>Derivatives And Other Financial Instruments - Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>62</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R63.htm</HtmlFileName>
      <LongName>2412402 - Disclosure - Fair Value Measures - Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/FairValueMeasuresAssetsAndLiabilitiesMeasuredAtFairValueOnRecurringBasisDetails</Role>
      <ShortName>Fair Value Measures - Assets and Liabilities Measured at Fair Value on a Recurring Basis (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>63</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R64.htm</HtmlFileName>
      <LongName>2412403 - Disclosure - Fair Value Measures - Fair Value of Financial Instruments (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/FairValueMeasuresFairValueOfFinancialInstrumentsDetails</Role>
      <ShortName>Fair Value Measures - Fair Value of Financial Instruments (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>64</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R65.htm</HtmlFileName>
      <LongName>2412404 - Disclosure - Fair Value Measures - Fair Value, Other Disclosures (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/FairValueMeasuresFairValueOtherDisclosuresDetails</Role>
      <ShortName>Fair Value Measures - Fair Value, Other Disclosures (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>65</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R66.htm</HtmlFileName>
      <LongName>2413402 - Disclosure - Income Taxes - Income Taxes by Location (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/IncomeTaxesIncomeTaxesByLocationDetails</Role>
      <ShortName>Income Taxes - Income Taxes by Location (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>66</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R67.htm</HtmlFileName>
      <LongName>2413403 - Disclosure - Income Taxes - Reconciliation of Income Taxes at U.S. Federal Statutory Rate (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/IncomeTaxesReconciliationOfIncomeTaxesAtUSFederalStatutoryRateDetails</Role>
      <ShortName>Income Taxes - Reconciliation of Income Taxes at U.S. Federal Statutory Rate (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>67</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R68.htm</HtmlFileName>
      <LongName>2413404 - Disclosure - Income Taxes - Schedule of Deferred Taxes (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/IncomeTaxesScheduleOfDeferredTaxesDetails</Role>
      <ShortName>Income Taxes - Schedule of Deferred Taxes (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>68</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R69.htm</HtmlFileName>
      <LongName>2413405 - Disclosure - Income Taxes - Unrecognized Tax Benefits (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/IncomeTaxesUnrecognizedTaxBenefitsDetails</Role>
      <ShortName>Income Taxes - Unrecognized Tax Benefits (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>69</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R70.htm</HtmlFileName>
      <LongName>2413406 - Disclosure - Income Taxes - Income Taxes Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/IncomeTaxesIncomeTaxesNarrativeDetails</Role>
      <ShortName>Income Taxes - Income Taxes Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>70</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R71.htm</HtmlFileName>
      <LongName>2414402 - Disclosure - Benefit Obligations - Benefit Obligations Narrative (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/BenefitObligationsBenefitObligationsNarrativeDetails</Role>
      <ShortName>Benefit Obligations - Benefit Obligations Narrative (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>71</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R72.htm</HtmlFileName>
      <LongName>2414403 - Disclosure - Benefit Obligations - Change in Benefit Obligation and Fair Value (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/BenefitObligationsChangeInBenefitObligationAndFairValueDetails</Role>
      <ShortName>Benefit Obligations - Change in Benefit Obligation and Fair Value (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>72</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R73.htm</HtmlFileName>
      <LongName>2414404 - Disclosure - Benefit Obligation - Excess of Plan Assets (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/BenefitObligationExcessOfPlanAssetsDetails</Role>
      <ShortName>Benefit Obligation - Excess of Plan Assets (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>73</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R74.htm</HtmlFileName>
      <LongName>2414405 - Disclosure - Benefit Obligations - Future Payments (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/BenefitObligationsFuturePaymentsDetails</Role>
      <ShortName>Benefit Obligations - Future Payments (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>74</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R75.htm</HtmlFileName>
      <LongName>2414406 - Disclosure - Benefit Obligations (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/BenefitObligationsDetails</Role>
      <ShortName>Benefit Obligations (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.avaya.com/role/BenefitObligationsTables</ParentRole>
      <Position>75</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R76.htm</HtmlFileName>
      <LongName>2414407 - Disclosure - Benefit Obligations - Other Comprehensive Income (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/BenefitObligationsOtherComprehensiveIncomeDetails</Role>
      <ShortName>Benefit Obligations - Other Comprehensive Income (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>76</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R77.htm</HtmlFileName>
      <LongName>2414408 - Disclosure - Benefit Obligations - Amortized in Next Fiscal Year (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/BenefitObligationsAmortizedInNextFiscalYearDetails</Role>
      <ShortName>Benefit Obligations - Amortized in Next Fiscal Year (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>77</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R78.htm</HtmlFileName>
      <LongName>2414409 - Disclosure - Benefit Obligations - Weighted Average Assumptions Used (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/BenefitObligationsWeightedAverageAssumptionsUsedDetails</Role>
      <ShortName>Benefit Obligations - Weighted Average Assumptions Used (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>78</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R79.htm</HtmlFileName>
      <LongName>2414410 - Disclosure - Benefit Obligations - Health Care Cost Trends (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/BenefitObligationsHealthCareCostTrendsDetails</Role>
      <ShortName>Benefit Obligations - Health Care Cost Trends (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>79</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R80.htm</HtmlFileName>
      <LongName>2414411 - Disclosure - Benefit Obligations - Pension Plan Allocation (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/BenefitObligationsPensionPlanAllocationDetails</Role>
      <ShortName>Benefit Obligations - Pension Plan Allocation (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>80</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R81.htm</HtmlFileName>
      <LongName>2414412 - Disclosure - Benefit Obligations - Fair Value of the U.S. Pension Plans Assets by Asset Class (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/BenefitObligationsFairValueOfUSPensionPlansAssetsByAssetClassDetails</Role>
      <ShortName>Benefit Obligations - Fair Value of the U.S. Pension Plans Assets by Asset Class (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>81</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R82.htm</HtmlFileName>
      <LongName>2414413 - Disclosure - Benefit Obligations - Level 3 Rollforward (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/BenefitObligationsLevel3RollforwardDetails</Role>
      <ShortName>Benefit Obligations - Level 3 Rollforward (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>82</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R83.htm</HtmlFileName>
      <LongName>2414414 - Disclosure - Benefit Obligations - Fair Value of the Non-U.S. Pension Plan Assets and Postretirement by Asset Class (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/BenefitObligationsFairValueOfNonUSPensionPlanAssetsAndPostretirementByAssetClassDetails</Role>
      <ShortName>Benefit Obligations - Fair Value of the Non-U.S. Pension Plan Assets and Postretirement by Asset Class (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>83</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R84.htm</HtmlFileName>
      <LongName>2415402 - Disclosure - Share-Based Compensation (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/ShareBasedCompensationDetails</Role>
      <ShortName>Share-Based Compensation (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.avaya.com/role/ShareBasedCompensationTables</ParentRole>
      <Position>84</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R85.htm</HtmlFileName>
      <LongName>2415403 - Disclosure - Share-Based Compensation  - Options Outstanding (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/ShareBasedCompensationOptionsOutstandingDetails</Role>
      <ShortName>Share-Based Compensation  - Options Outstanding (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>85</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R86.htm</HtmlFileName>
      <LongName>2415404 - Disclosure - Share-Based Compensation  - Valuations Assumptions (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/ShareBasedCompensationValuationsAssumptionsDetails</Role>
      <ShortName>Share-Based Compensation  - Valuations Assumptions (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>86</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R87.htm</HtmlFileName>
      <LongName>2415405 - Disclosure - Share-Based Compensation  - Nonvested Shares (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/ShareBasedCompensationNonvestedSharesDetails</Role>
      <ShortName>Share-Based Compensation  - Nonvested Shares (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>87</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R88.htm</HtmlFileName>
      <LongName>2416402 - Disclosure - Reportable Segments (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/ReportableSegmentsDetails</Role>
      <ShortName>Reportable Segments (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.avaya.com/role/ReportableSegmentsTables</ParentRole>
      <Position>88</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R89.htm</HtmlFileName>
      <LongName>2416403 - Disclosure - Reportable Segments - Revenues from External Customers and Long-Lived Assets (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/ReportableSegmentsRevenuesFromExternalCustomersAndLongLivedAssetsDetails</Role>
      <ShortName>Reportable Segments - Revenues from External Customers and Long-Lived Assets (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>89</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R90.htm</HtmlFileName>
      <LongName>2417402 - Disclosure - Accumulated Other Comprehensive Loss (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/AccumulatedOtherComprehensiveLossDetails</Role>
      <ShortName>Accumulated Other Comprehensive Loss (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.avaya.com/role/AccumulatedOtherComprehensiveLossTables</ParentRole>
      <Position>90</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R91.htm</HtmlFileName>
      <LongName>2418401 - Disclosure - Related Party Transactions (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/RelatedPartyTransactionsDetails</Role>
      <ShortName>Related Party Transactions (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.avaya.com/role/RelatedPartyTransactions</ParentRole>
      <Position>91</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R92.htm</HtmlFileName>
      <LongName>2419402 - Disclosure - Commitments And Contingencies - Movement in product warranty liability (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/CommitmentsAndContingenciesMovementInProductWarrantyLiabilityDetails</Role>
      <ShortName>Commitments And Contingencies - Movement in product warranty liability (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>92</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R93.htm</HtmlFileName>
      <LongName>2419403 - Disclosure - Commitments And Contingencies - Commitments and Contingencies, other disclosures (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/CommitmentsAndContingenciesCommitmentsAndContingenciesOtherDisclosuresDetails</Role>
      <ShortName>Commitments And Contingencies - Commitments and Contingencies, other disclosures (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <Position>93</Position>
    </Report>
    <Report instance="cik0001116521-20150930.xml">
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <HtmlFileName>R94.htm</HtmlFileName>
      <LongName>2420402 - Disclosure - Quarterly Information (unaudited) (Details)</LongName>
      <ReportType>Sheet</ReportType>
      <Role>http://www.avaya.com/role/QuarterlyInformationUnauditedDetails</Role>
      <ShortName>Quarterly Information (unaudited) (Details)</ShortName>
      <MenuCategory>Details</MenuCategory>
      <ParentRole>http://www.avaya.com/role/QuarterlyInformationUnauditedTables</ParentRole>
      <Position>94</Position>
    </Report>
    <Report>
      <IsDefault>false</IsDefault>
      <HasEmbeddedReports>false</HasEmbeddedReports>
      <LongName>All Reports</LongName>
      <ReportType>Book</ReportType>
      <ShortName>All Reports</ShortName>
    </Report>
  </MyReports>
  <Logs>
    <Log type="Info">In ''Consolidated Statements Of Operations'', column(s) 1, 2, 3, 4, 5, 6, 7, 8 are contained in other reports, so were removed by flow through suppression.</Log>
    <Log type="Info">In ''Consolidated Statements of Comprehensive Loss Statement'', column(s) 1, 2, 3, 4, 5, 6, 7, 8 are contained in other reports, so were removed by flow through suppression.</Log>
    <Log type="Info">In ''Consolidated Balance Sheets'', column(s) 3, 4 are contained in other reports, so were removed by flow through suppression.</Log>
    <Log type="Info">In ''Consolidated Statements of Changes in Stockholder's Deficiency'', column(s) 2, 3, 6, 7 are contained in other reports, so were removed by flow through suppression.</Log>
    <Log type="Info">In ''Consolidated Statements Of Cash Flows'', column(s) 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13 are contained in other reports, so were removed by flow through suppression.</Log>
  </Logs>
  <InputFiles>
    <File>cik0001116521-20150930.xml</File>
    <File>cik0001116521-20150930_cal.xml</File>
    <File>cik0001116521-20150930_def.xml</File>
    <File>cik0001116521-20150930_lab.xml</File>
    <File>cik0001116521-20150930_pre.xml</File>
    <File>cik0001116521-20150930.xsd</File>
  </InputFiles>
  <SupplementalFiles/>
  <BaseTaxonomies/>
  <HasPresentationLinkbase>true</HasPresentationLinkbase>
  <HasCalculationLinkbase>true</HasCalculationLinkbase>
</FilingSummary>

