| | | | | | | | | | | | | | | | | | | | | |
<?xml version="1.0" encoding="windows-1252"?> |
<FilingSummary xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema"> |
| <Version> 2.4.0.6 </Version> |
| <ProcessingTime/> |
| <ReportFormat> Html </ReportFormat> |
| <ContextCount> 313 </ContextCount> |
| <ElementCount> 578 </ElementCount> |
| <EntityCount> 1 </EntityCount> |
| <FootnotesReported> true </FootnotesReported> |
| <SegmentCount> 85 </SegmentCount> |
| <ScenarioCount> 0 </ScenarioCount> |
| <TuplesReported> false </TuplesReported> |
| <UnitCount> 11 </UnitCount> |
| <MyReports> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R1.htm </HtmlFileName> |
| | | <LongName> 101 - Document - Document and Entity Information </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/DocumentDocumentandEntityInformation </Role> |
| | | <ShortName> Document and Entity Information </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> true </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R2.htm </HtmlFileName> |
| | | <LongName> 103 - Statement - CONSOLIDATED BALANCE SHEETS </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/StatementOfFinancialPositionClassified </Role> |
| | | <ShortName> CONSOLIDATED BALANCE SHEETS </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R3.htm </HtmlFileName> |
| | | <LongName> 104 - Statement - CONSOLIDATED BALANCE SHEETS (Parenthetical) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/StatementOfFinancialPositionClassifiedParenthetical </Role> |
| | | <ShortName> CONSOLIDATED BALANCE SHEETS (Parenthetical) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R4.htm </HtmlFileName> |
| | | <LongName> 105 - Statement - CONSOLIDATED STATEMENTS OF INCOME </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/StatementOfIncome </Role> |
| | | <ShortName> CONSOLIDATED STATEMENTS OF INCOME </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R5.htm </HtmlFileName> |
| | | <LongName> 106 - Statement - CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/StatementOfOtherComprehensiveIncome </Role> |
| | | <ShortName> CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R6.htm </HtmlFileName> |
| | | <LongName> 107 - Statement - CONSOLIDATED STATEMENTS OF EQUITY </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/StatementOfShareholdersEquityAndOtherComprehensiveIncome </Role> |
| | | <ShortName> CONSOLIDATED STATEMENTS OF EQUITY </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R7.htm </HtmlFileName> |
| | | <LongName> 108 - Statement - CONSOLIDATED STATEMENTS OF EQUITY (Parenthetical) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/StatementOfShareholdersEquityAndOtherComprehensiveIncomeParenthetical </Role> |
| | | <ShortName> CONSOLIDATED STATEMENTS OF EQUITY (Parenthetical) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R8.htm </HtmlFileName> |
| | | <LongName> 109 - Statement - CONSOLIDATED STATEMENTS OF CASH FLOWS </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/StatementOfCashFlowsIndirect </Role> |
| | | <ShortName> CONSOLIDATED STATEMENTS OF CASH FLOWS </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R9.htm </HtmlFileName> |
| | | <LongName> 110 - Disclosure - Description of Business and Summary of Significant Accounting Policies </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/NotesToFinancialStatementsOrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureAndSignificantAccountingPoliciesTextBlock </Role> |
| | | <ShortName> Description of Business and Summary of Significant Accounting Policies </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R10.htm </HtmlFileName> |
| | | <LongName> 111 - Disclosure - Discontinued Operations </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/NotesToFinancialStatementsDisposalGroupsIncludingDiscontinuedOperationsDisclosureTextBlock </Role> |
| | | <ShortName> Discontinued Operations </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R11.htm </HtmlFileName> |
| | | <LongName> 112 - Disclosure - Fair Value Measurements </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/NotesToFinancialStatementsFairValueDisclosuresTextBlock </Role> |
| | | <ShortName> Fair Value Measurements </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R12.htm </HtmlFileName> |
| | | <LongName> 113 - Disclosure - Property, Plant and Equipment </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/NotesToFinancialStatementsPropertyPlantAndEquipmentTextBlock </Role> |
| | | <ShortName> Property, Plant and Equipment </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R13.htm </HtmlFileName> |
| | | <LongName> 114 - Disclosure - Goodwill and Other Intangibles </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/NotesToFinancialStatementsGoodwillAndIntangibleAssetsDisclosureTextBlock </Role> |
| | | <ShortName> Goodwill and Other Intangibles </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R14.htm </HtmlFileName> |
| | | <LongName> 115 - Disclosure - Other Operating (Losses) Gains, Net </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/NotesToFinancialStatementsOtherOperatingGainsLossNetTextBlock </Role> |
| | | <ShortName> Other Operating (Losses) Gains, Net </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R15.htm </HtmlFileName> |
| | | <LongName> 116 - Disclosure - Notes Payable </LongName> |
| | | <ReportType> Notes </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/NotesToFinancialStatementsLongTermDebtTextBlock </Role> |
| | | <ShortName> Notes Payable </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R16.htm </HtmlFileName> |
| | | <LongName> 117 - Disclosure - Other (Expense) Income, Net </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/NotesToFinancialStatementsOtherIncomeAndOtherExpenseDisclosureTextBlock </Role> |
| | | <ShortName> Other (Expense) Income, Net </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R17.htm </HtmlFileName> |
| | | <LongName> 118 - Disclosure - Income Taxes </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/NotesToFinancialStatementsIncomeTaxDisclosureTextBlock </Role> |
| | | <ShortName> Income Taxes </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R18.htm </HtmlFileName> |
| | | <LongName> 119 - Disclosure - Equity </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/NotesToFinancialStatementsEquityTextBlock </Role> |
| | | <ShortName> Equity </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R19.htm </HtmlFileName> |
| | | <LongName> 120 - Disclosure - Stock-Based Compensation </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/NotesToFinancialStatementsDisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlock </Role> |
| | | <ShortName> Stock-Based Compensation </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R20.htm </HtmlFileName> |
| | | <LongName> 121 - Disclosure - Accumulated Other Comprehensive Income (Loss) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/NotesToFinancialStatementsAccumulatedOtherComprehensiveIncomeLossDisclosureTextBlock </Role> |
| | | <ShortName> Accumulated Other Comprehensive Income (Loss) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R21.htm </HtmlFileName> |
| | | <LongName> 122 - Disclosure - Legal Proceedings </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/NotesToFinancialStatementsLegalMattersAndContingenciesTextBlock </Role> |
| | | <ShortName> Legal Proceedings </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R22.htm </HtmlFileName> |
| | | <LongName> 123 - Disclosure - Commitments and Contingencies </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/NotesToFinancialStatementsCommitmentsAndContingenciesDisclosureTextBlock </Role> |
| | | <ShortName> Commitments and Contingencies </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R23.htm </HtmlFileName> |
| | | <LongName> 124 - Disclosure - Related Party Transactions </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/NotesToFinancialStatementsRelatedPartyTransactionsDisclosureTextBlock </Role> |
| | | <ShortName> Related Party Transactions </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R24.htm </HtmlFileName> |
| | | <LongName> 125 - Disclosure - Defined Contribution Plans </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/NotesToFinancialStatementsDefinedContributionPlanDisclosureTextBlock </Role> |
| | | <ShortName> Defined Contribution Plans </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R25.htm </HtmlFileName> |
| | | <LongName> 126 - Disclosure - Business Segment Information </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/NotesToFinancialStatementsSegmentReportingDisclosureTextBlock </Role> |
| | | <ShortName> Business Segment Information </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R26.htm </HtmlFileName> |
| | | <LongName> 127 - Disclosure - Selected Quarterly Financial Data (Unaudited) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/NotesToFinancialStatementsQuarterlyFinancialInformationTextBlock </Role> |
| | | <ShortName> Selected Quarterly Financial Data (Unaudited) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R27.htm </HtmlFileName> |
| | | <LongName> 128 - Disclosure - Description of Business and Summary of Significant Accounting Policies (Policies) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/NotesToFinancialStatementsOrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureAndSignificantAccountingPoliciesTextBlockPolicies </Role> |
| | | <ShortName> Description of Business and Summary of Significant Accounting Policies (Policies) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R28.htm </HtmlFileName> |
| | | <LongName> 129 - Disclosure - Description of Business and Summary of Significant Accounting Policies (Tables) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/NotesToFinancialStatementsOrganizationConsolidationAndPresentationOfFinancialStatementsDisclosureAndSignificantAccountingPoliciesTextBlockTables </Role> |
| | | <ShortName> Description of Business and Summary of Significant Accounting Policies (Tables) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R29.htm </HtmlFileName> |
| | | <LongName> 130 - Disclosure - Discontinued Operations (Tables) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/NotesToFinancialStatementsDisposalGroupsIncludingDiscontinuedOperationsDisclosureTextBlockTables </Role> |
| | | <ShortName> Discontinued Operations (Tables) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R30.htm </HtmlFileName> |
| | | <LongName> 131 - Disclosure - Fair Value Measurements (Tables) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/NotesToFinancialStatementsFairValueDisclosuresTextBlockTables </Role> |
| | | <ShortName> Fair Value Measurements (Tables) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R31.htm </HtmlFileName> |
| | | <LongName> 132 - Disclosure - Property, Plant and Equipment (Tables) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/NotesToFinancialStatementsPropertyPlantAndEquipmentTextBlockTables </Role> |
| | | <ShortName> Property, Plant and Equipment (Tables) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R32.htm </HtmlFileName> |
| | | <LongName> 133 - Disclosure - Goodwill and Other Intangibles (Tables) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/NotesToFinancialStatementsGoodwillAndIntangibleAssetsDisclosureTextBlockTables </Role> |
| | | <ShortName> Goodwill and Other Intangibles (Tables) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R33.htm </HtmlFileName> |
| | | <LongName> 134 - Disclosure - Other Operating (Losses) Gains, Net (Tables) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/NotesToFinancialStatementsOtherOperatingGainsLossNetTextBlockTables </Role> |
| | | <ShortName> Other Operating (Losses) Gains, Net (Tables) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R34.htm </HtmlFileName> |
| | | <LongName> 135 - Disclosure - Notes Payable (Tables) </LongName> |
| | | <ReportType> Notes </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/NotesToFinancialStatementsLongTermDebtTextBlockTables </Role> |
| | | <ShortName> Notes Payable (Tables) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R35.htm </HtmlFileName> |
| | | <LongName> 136 - Disclosure - Other (Expense) Income, Net (Tables) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/NotesToFinancialStatementsOtherIncomeAndOtherExpenseDisclosureTextBlockTables </Role> |
| | | <ShortName> Other (Expense) Income, Net (Tables) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R36.htm </HtmlFileName> |
| | | <LongName> 137 - Disclosure - Income Taxes (Tables) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/NotesToFinancialStatementsIncomeTaxDisclosureTextBlockTables </Role> |
| | | <ShortName> Income Taxes (Tables) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R37.htm </HtmlFileName> |
| | | <LongName> 138 - Disclosure - Stock-Based Compensation (Tables) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/NotesToFinancialStatementsDisclosureOfCompensationRelatedCostsShareBasedPaymentsTextBlockTables </Role> |
| | | <ShortName> Stock-Based Compensation (Tables) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R38.htm </HtmlFileName> |
| | | <LongName> 139 - Disclosure - Accumulated Other Comprehensive Income (Loss) (Tables) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/NotesToFinancialStatementsAccumulatedOtherComprehensiveIncomeLossDisclosureTextBlockTables </Role> |
| | | <ShortName> Accumulated Other Comprehensive Income (Loss) (Tables) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R39.htm </HtmlFileName> |
| | | <LongName> 140 - Disclosure - Commitments and Contingencies (Tables) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/NotesToFinancialStatementsCommitmentsAndContingenciesDisclosureTextBlockTables </Role> |
| | | <ShortName> Commitments and Contingencies (Tables) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R40.htm </HtmlFileName> |
| | | <LongName> 141 - Disclosure - Business Segment Information (Tables) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/NotesToFinancialStatementsSegmentReportingDisclosureTextBlockTables </Role> |
| | | <ShortName> Business Segment Information (Tables) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R41.htm </HtmlFileName> |
| | | <LongName> 142 - Disclosure - Selected Quarterly Financial Data (Unaudited) (Tables) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/NotesToFinancialStatementsQuarterlyFinancialInformationTextBlockTables </Role> |
| | | <ShortName> Selected Quarterly Financial Data (Unaudited) (Tables) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R42.htm </HtmlFileName> |
| | | <LongName> 143 - Disclosure - Description of Business and Summary of Significant Accounting Policies - Additional Information (Detail) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/DisclosureDescriptionOfBusinessAndSummaryOfSignificantAccountingPoliciesAdditionalInformation </Role> |
| | | <ShortName> Description of Business and Summary of Significant Accounting Policies - Additional Information (Detail) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R43.htm </HtmlFileName> |
| | | <LongName> 144 - Disclosure - Description of Business and Summary of Significant Accounting Policies - Summary of Weighted-Average Number of Shares used in Calculation of Basic and Diluted Earnings Per Share (Detail) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/DisclosureDescriptionOfBusinessAndSummaryOfSignificantAccountingPoliciesSummaryOfWeightedAverageNumberOfSharesUsedInCalculationOfBasicAndDilutedEarningsPerShare </Role> |
| | | <ShortName> Description of Business and Summary of Significant Accounting Policies - Summary of Weighted-Average Number of Shares used in Calculation of Basic and Diluted Earnings Per Share (Detail) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R44.htm </HtmlFileName> |
| | | <LongName> 145 - Disclosure - Description of Business and Summary of Significant Accounting Policies - Summary of Outstanding Stock Options Excluded from Calculation of Diluted Earnings Per Share (Detail) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/DisclosureDescriptionOfBusinessAndSummaryOfSignificantAccountingPoliciesSummaryOfOutstandingStockOptionsExcludedFromCalculationOfDilutedEarningsPerShare </Role> |
| | | <ShortName> Description of Business and Summary of Significant Accounting Policies - Summary of Outstanding Stock Options Excluded from Calculation of Diluted Earnings Per Share (Detail) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R45.htm </HtmlFileName> |
| | | <LongName> 146 - Disclosure - Description of Business and Summary of Significant Accounting Policies - Summary of Change in Allowance for Doubtful Accounts (Detail) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/DisclosureDescriptionOfBusinessAndSummaryOfSignificantAccountingPoliciesSummaryOfChangeInAllowanceForDoubtfulAccounts </Role> |
| | | <ShortName> Description of Business and Summary of Significant Accounting Policies - Summary of Change in Allowance for Doubtful Accounts (Detail) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R46.htm </HtmlFileName> |
| | | <LongName> 147 - Disclosure - Discontinued Operations - Additional Information (Detail) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/DisclosureDiscontinuedOperationsAdditionalInformation </Role> |
| | | <ShortName> Discontinued Operations - Additional Information (Detail) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R47.htm </HtmlFileName> |
| | | <LongName> 148 - Disclosure - Discontinued Operations - Summary Financial Data of Discontinued Operations (Detail) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/DisclosureDiscontinuedOperationsSummaryFinancialDataOfDiscontinuedOperations </Role> |
| | | <ShortName> Discontinued Operations - Summary Financial Data of Discontinued Operations (Detail) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R48.htm </HtmlFileName> |
| | | <LongName> 149 - Disclosure - Discontinued Operations - Schedule of Assets and Liabilities of Discontinued Operations (Detail) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/DisclosureDiscontinuedOperationsScheduleOfAssetsAndLiabilitiesOfDiscontinuedOperations </Role> |
| | | <ShortName> Discontinued Operations - Schedule of Assets and Liabilities of Discontinued Operations (Detail) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R49.htm </HtmlFileName> |
| | | <LongName> 150 - Disclosure - Fair Value Measurements - Additional Information (Detail) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/DisclosureFairValueMeasurementsAdditionalInformation </Role> |
| | | <ShortName> Fair Value Measurements - Additional Information (Detail) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R50.htm </HtmlFileName> |
| | | <LongName> 151 - Disclosure - Fair Value Measurements - Summary of Change in Company's Assets Measured at Fair Value on Recurring Basis (Detail) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/DisclosureFairValueMeasurementsSummaryOfChangeInCompanysAssetsMeasuredAtFairValueOnRecurringBasis </Role> |
| | | <ShortName> Fair Value Measurements - Summary of Change in Company's Assets Measured at Fair Value on Recurring Basis (Detail) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R51.htm </HtmlFileName> |
| | | <LongName> 152 - Disclosure - Property, Plant and Equipment - Schedule of Property, Plant and Equipment (Detail) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/DisclosurePropertyPlantAndEquipmentScheduleOfPropertyPlantAndEquipment </Role> |
| | | <ShortName> Property, Plant and Equipment - Schedule of Property, Plant and Equipment (Detail) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R52.htm </HtmlFileName> |
| | | <LongName> 153 - Disclosure - Property, Plant and Equipment - Additional Information (Detail) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/DisclosurePropertyPlantAndEquipmentAdditionalInformation </Role> |
| | | <ShortName> Property, Plant and Equipment - Additional Information (Detail) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R53.htm </HtmlFileName> |
| | | <LongName> 154 - Disclosure - Goodwill and Other Intangibles - Schedule of Change in Carrying Amount of Goodwill by Operating Segment (Detail) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/DisclosureGoodwillAndOtherIntangiblesScheduleOfChangeInCarryingAmountOfGoodwillByOperatingSegment </Role> |
| | | <ShortName> Goodwill and Other Intangibles - Schedule of Change in Carrying Amount of Goodwill by Operating Segment (Detail) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R54.htm </HtmlFileName> |
| | | <LongName> 155 - Disclosure - Goodwill and Other Intangibles - Schedule of Other Intangible Assets (Detail) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/DisclosureGoodwillAndOtherIntangiblesScheduleOfOtherIntangibleAssets </Role> |
| | | <ShortName> Goodwill and Other Intangibles - Schedule of Other Intangible Assets (Detail) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R55.htm </HtmlFileName> |
| | | <LongName> 156 - Disclosure - Goodwill and Other Intangibles - Additional Information (Detail) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/DisclosureGoodwillAndOtherIntangiblesAdditionalInformation </Role> |
| | | <ShortName> Goodwill and Other Intangibles - Additional Information (Detail) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R56.htm </HtmlFileName> |
| | | <LongName> 157 - Disclosure - Other Operating (Losses) Gains, Net - Summary of Other Operating (Losses) Gains, Net by Business Segment (Detail) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/DisclosureOtherOperatingLossesGainsNetSummaryOfOtherOperatingLossesGainsNetByBusinessSegment </Role> |
| | | <ShortName> Other Operating (Losses) Gains, Net - Summary of Other Operating (Losses) Gains, Net by Business Segment (Detail) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R57.htm </HtmlFileName> |
| | | <LongName> 158 - Disclosure - Notes Payable - Schedule of Notes Payable (Detail) </LongName> |
| | | <ReportType> Notes </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/DisclosureNotesPayableScheduleOfNotesPayable </Role> |
| | | <ShortName> Notes Payable - Schedule of Notes Payable (Detail) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R58.htm </HtmlFileName> |
| | | <LongName> 159 - Disclosure - Notes Payable - Schedule of Notes Payable (Parenthetical) (Detail) </LongName> |
| | | <ReportType> Notes </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/DisclosureNotesPayableScheduleOfNotesPayableParenthetical </Role> |
| | | <ShortName> Notes Payable - Schedule of Notes Payable (Parenthetical) (Detail) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R59.htm </HtmlFileName> |
| | | <LongName> 160 - Disclosure - Notes Payable - Schedule of Estimated Future Principal Payments of Notes Payable (Detail) </LongName> |
| | | <ReportType> Notes </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/DisclosureNotesPayableScheduleOfEstimatedFuturePrincipalPaymentsOfNotesPayable </Role> |
| | | <ShortName> Notes Payable - Schedule of Estimated Future Principal Payments of Notes Payable (Detail) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R60.htm </HtmlFileName> |
| | | <LongName> 161 - Disclosure - Other (Expense) Income, Net - Schedule of Other Income Expense Net (Detail) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/DisclosureOtherExpenseIncomeNetScheduleOfOtherIncomeExpenseNet </Role> |
| | | <ShortName> Other (Expense) Income, Net - Schedule of Other Income Expense Net (Detail) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R61.htm </HtmlFileName> |
| | | <LongName> 162 - Disclosure - Other (Expense) Income, Net - Additional Information (Detail) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/DisclosureOtherExpenseIncomeNetAdditionalInformation </Role> |
| | | <ShortName> Other (Expense) Income, Net - Additional Information (Detail) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R62.htm </HtmlFileName> |
| | | <LongName> 163 - Disclosure - Income Taxes - Schedule of Income (Loss) from Continuing Operations Before Income Taxes (Detail) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/DisclosureIncomeTaxesScheduleOfIncomeLossFromContinuingOperationsBeforeIncomeTaxes </Role> |
| | | <ShortName> Income Taxes - Schedule of Income (Loss) from Continuing Operations Before Income Taxes (Detail) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R63.htm </HtmlFileName> |
| | | <LongName> 164 - Disclosure - Income Taxes - Schedule of Deferred Income Tax Assets and Deferred Income Tax Liabilities (Detail) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/DisclosureIncomeTaxesScheduleOfDeferredIncomeTaxAssetsAndDeferredIncomeTaxLiabilities </Role> |
| | | <ShortName> Income Taxes - Schedule of Deferred Income Tax Assets and Deferred Income Tax Liabilities (Detail) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R64.htm </HtmlFileName> |
| | | <LongName> 165 - Disclosure - Income Taxes - Schedule of Benefit from Income Taxes (Detail) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/DisclosureIncomeTaxesScheduleOfBenefitFromIncomeTaxes </Role> |
| | | <ShortName> Income Taxes - Schedule of Benefit from Income Taxes (Detail) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R65.htm </HtmlFileName> |
| | | <LongName> 166 - Disclosure - Income Taxes - Additional Information (Detail) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/DisclosureIncomeTaxesAdditionalInformation </Role> |
| | | <ShortName> Income Taxes - Additional Information (Detail) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R66.htm </HtmlFileName> |
| | | <LongName> 167 - Disclosure - Income Taxes - Schedule of Statutory Income Tax Rate and Income Taxes Provided (Detail) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/DisclosureIncomeTaxesScheduleOfStatutoryIncomeTaxRateAndIncomeTaxesProvided </Role> |
| | | <ShortName> Income Taxes - Schedule of Statutory Income Tax Rate and Income Taxes Provided (Detail) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R67.htm </HtmlFileName> |
| | | <LongName> 168 - Disclosure - Income Taxes - Schedule of Change in Valuation Allowance (Detail) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/DisclosureIncomeTaxesScheduleOfChangeInValuationAllowance </Role> |
| | | <ShortName> Income Taxes - Schedule of Change in Valuation Allowance (Detail) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R68.htm </HtmlFileName> |
| | | <LongName> 169 - Disclosure - Income Taxes - Summary of Change in Balance of Unrecognized Income Tax Benefits (Detail) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/DisclosureIncomeTaxesSummaryOfChangeInBalanceOfUnrecognizedIncomeTaxBenefits </Role> |
| | | <ShortName> Income Taxes - Summary of Change in Balance of Unrecognized Income Tax Benefits (Detail) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R69.htm </HtmlFileName> |
| | | <LongName> 170 - Disclosure - Equity - Additional Information (Detail) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/DisclosureEquityAdditionalInformation </Role> |
| | | <ShortName> Equity - Additional Information (Detail) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R70.htm </HtmlFileName> |
| | | <LongName> 171 - Disclosure - Stock-Based Compensation - Additional Information (Detail) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/DisclosureStockBasedCompensationAdditionalInformation </Role> |
| | | <ShortName> Stock-Based Compensation - Additional Information (Detail) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R71.htm </HtmlFileName> |
| | | <LongName> 172 - Disclosure - Stock-Based Compensation - Schedule of Risk Free Rate Based on U.S. Treasury Yield Curve Effect at Time of Grant (Detail) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/DisclosureStockBasedCompensationScheduleOfRiskFreeRateBasedOnUSTreasuryYieldCurveEffectAtTimeOfGrant </Role> |
| | | <ShortName> Stock-Based Compensation - Schedule of Risk Free Rate Based on U.S. Treasury Yield Curve Effect at Time of Grant (Detail) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R72.htm </HtmlFileName> |
| | | <LongName> 173 - Disclosure - Stock-Based Compensation - Summary of Stock Option Activity (Detail) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/DisclosureStockBasedCompensationSummaryOfStockOptionActivity </Role> |
| | | <ShortName> Stock-Based Compensation - Summary of Stock Option Activity (Detail) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R73.htm </HtmlFileName> |
| | | <LongName> 174 - Disclosure - Stock-Based Compensation - Grants of Restricted Shares of Class B Common Stock (Detail) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/DisclosureStockBasedCompensationGrantsOfRestrictedSharesOfClassBCommonStock </Role> |
| | | <ShortName> Stock-Based Compensation - Grants of Restricted Shares of Class B Common Stock (Detail) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R74.htm </HtmlFileName> |
| | | <LongName> 175 - Disclosure - Accumulated Other Comprehensive Income (Loss) - Schedule of Accumulated Balances for Each Classification of Other Comprehensive Income (Detail) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/DisclosureAccumulatedOtherComprehensiveIncomeLossScheduleOfAccumulatedBalancesForEachClassificationOfOtherComprehensiveIncome </Role> |
| | | <ShortName> Accumulated Other Comprehensive Income (Loss) - Schedule of Accumulated Balances for Each Classification of Other Comprehensive Income (Detail) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R75.htm </HtmlFileName> |
| | | <LongName> 176 - Disclosure - Legal Proceedings - Additional Information (Detail) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/DisclosureLegalProceedingsAdditionalInformation </Role> |
| | | <ShortName> Legal Proceedings - Additional Information (Detail) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R76.htm </HtmlFileName> |
| | | <LongName> 177 - Disclosure - Commitments and Contingencies - Additional Information (Detail) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/DisclosureCommitmentsAndContingenciesAdditionalInformation </Role> |
| | | <ShortName> Commitments and Contingencies - Additional Information (Detail) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R77.htm </HtmlFileName> |
| | | <LongName> 178 - Disclosure - Commitments and Contingencies - Future Minimum Payments for Operating Leases (Detail) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/DisclosureCommitmentsAndContingenciesFutureMinimumPaymentsForOperatingLeases </Role> |
| | | <ShortName> Commitments and Contingencies - Future Minimum Payments for Operating Leases (Detail) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R78.htm </HtmlFileName> |
| | | <LongName> 179 - Disclosure - Commitments and Contingencies - Restricted Cash and Cash Equivalents (Detail) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/DisclosureCommitmentsAndContingenciesRestrictedCashAndCashEquivalents </Role> |
| | | <ShortName> Commitments and Contingencies - Restricted Cash and Cash Equivalents (Detail) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R79.htm </HtmlFileName> |
| | | <LongName> 180 - Disclosure - Related Party Transactions - Additional Information (Detail) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/DisclosureRelatedPartyTransactionsAdditionalInformation </Role> |
| | | <ShortName> Related Party Transactions - Additional Information (Detail) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R80.htm </HtmlFileName> |
| | | <LongName> 181 - Disclosure - Defined Contribution Plans - Additional Information (Detail) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/DisclosureDefinedContributionPlansAdditionalInformation </Role> |
| | | <ShortName> Defined Contribution Plans - Additional Information (Detail) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R81.htm </HtmlFileName> |
| | | <LongName> 182 - Disclosure - Business Segment Information - Additional Information (Detail) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/DisclosureBusinessSegmentInformationAdditionalInformation </Role> |
| | | <ShortName> Business Segment Information - Additional Information (Detail) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R82.htm </HtmlFileName> |
| | | <LongName> 183 - Disclosure - Business Segment Information - Operating Results of Business Segments (Detail) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/DisclosureBusinessSegmentInformationOperatingResultsOfBusinessSegments </Role> |
| | | <ShortName> Business Segment Information - Operating Results of Business Segments (Detail) </ShortName> |
| | | </Report> |
| | <Report> |
| | | <IsDefault> false </IsDefault> |
| | | <HasEmbeddedReports> false </HasEmbeddedReports> |
| | | <HtmlFileName> R83.htm </HtmlFileName> |
| | | <LongName> 184 - Disclosure - Selected Quarterly Financial Data (Unaudited) - Summary of Selected Quarterly Financial Data (Detail) </LongName> |
| | | <ReportType> Sheet </ReportType> |
| | | <Role> http://www.idt.net/taxonomy/role/DisclosureSelectedQuarterlyFinancialDataUnauditedSummaryOfSelectedQuarterlyFinancialData </Role> |
| | | <ShortName> Selected Quarterly Financial Data (Unaudited) - Summary of Selected Quarterly Financial Data (Detail) </ShortName> |
| | | </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"> Element idt_DefinedContributionPlanEmployerMatchingContributionInEmployerShares had a mix of decimals attribute values: -3 0. </Log> |
| | <Log type="Info"> Element idt_GainLossRelatedToSettlement had a mix of decimals attribute values: -5 -3. </Log> |
| | <Log type="Info"> Element idt_GainOnInsuranceSettlement had a mix of decimals attribute values: -5 -3. </Log> |
| | <Log type="Info"> Element idt_GainOnSettlement had a mix of decimals attribute values: -5 -3. </Log> |
| | <Log type="Info"> Element idt_LegalSettlementReflectCurrentEstimatedRangeOfLoss had a mix of decimals attribute values: -5 -3. </Log> |
| | <Log type="Info"> Element idt_PatentLitigationExpense had a mix of decimals attribute values: -5 -3. </Log> |
| | <Log type="Info"> Element us-gaap_GainLossOnContractTermination had a mix of decimals attribute values: -5 -3. </Log> |
| | <Log type="Info"> Element us-gaap_GainLossOnSaleOfOtherAssets had a mix of decimals attribute values: -5 -3. </Log> |
| | <Log type="Info"> Element us-gaap_GainLossRelatedToLitigationSettlement had a mix of decimals attribute values: -5 -3. </Log> |
| | <Log type="Info"> Element us-gaap_IncomeTaxExpenseBenefit had a mix of decimals attribute values: -5 -3. </Log> |
| | <Log type="Info"> Element us-gaap_ProceedsFromSaleOfBuildings had a mix of decimals attribute values: -5 -3. </Log> |
| | <Log type="Info"> Element us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionsExpectedVolatilityRate had a mix of decimals attribute values: 2 3. </Log> |
| | <Log type="Info"> 'Shares' elements on report '107 - Statement - CONSOLIDATED STATEMENTS OF EQUITY' had a mix of different decimal attribute values. </Log> |
| | <Log type="Info"> 'Monetary' elements on report '153 - Disclosure - Property, Plant and Equipment - Additional Information (Detail)' had a mix of different decimal attribute values. </Log> |
| | <Log type="Info"> 'Monetary' elements on report '157 - Disclosure - Other Operating (Losses) Gains, Net - Summary of Other Operating (Losses) Gains, Net by Business Segment (Detail)' had a mix of different decimal attribute values. </Log> |
| | <Log type="Info"> 'Monetary' elements on report '158 - Disclosure - Notes Payable - Schedule of Notes Payable (Detail)' had a mix of different decimal attribute values. </Log> |
| | <Log type="Info"> 'Monetary' elements on report '166 - Disclosure - Income Taxes - Additional Information (Detail)' had a mix of different decimal attribute values. </Log> |
| | <Log type="Info"> 'Monetary' elements on report '170 - Disclosure - Equity - Additional Information (Detail)' had a mix of different decimal attribute values. </Log> |
| | <Log type="Info"> 'Shares' elements on report '171 - Disclosure - Stock-Based Compensation - Additional Information (Detail)' had a mix of different decimal attribute values. </Log> |
| | <Log type="Info"> 'Monetary' elements on report '176 - Disclosure - Legal Proceedings - Additional Information (Detail)' had a mix of different decimal attribute values. </Log> |
| | <Log type="Info"> 'Monetary' elements on report '177 - Disclosure - Commitments and Contingencies - Additional Information (Detail)' had a mix of different decimal attribute values. </Log> |
| | <Log type="Info"> 'Monetary' elements on report '180 - Disclosure - Related Party Transactions - Additional Information (Detail)' had a mix of different decimal attribute values. </Log> |
| | <Log type="Info"> 'Monetary' elements on report '182 - Disclosure - Business Segment Information - Additional Information (Detail)' had a mix of different decimal attribute values. </Log> |
| | <Log type="Info"> 'Monetary' elements on report '184 - Disclosure - Selected Quarterly Financial Data (Unaudited) - Summary of Selected Quarterly Financial Data (Detail)' had a mix of different decimal attribute values. </Log> |
| | <Log type="Info"> Process Flow-Through: 103 - Statement - CONSOLIDATED BALANCE SHEETS </Log> |
| | <Log type="Info"> Process Flow-Through: Removing column 'Jul. 31, 2010' </Log> |
| | <Log type="Info"> Process Flow-Through: Removing column 'Jul. 31, 2009' </Log> |
| | <Log type="Info"> Process Flow-Through: 104 - Statement - CONSOLIDATED BALANCE SHEETS (Parenthetical) </Log> |
| | <Log type="Info"> Process Flow-Through: Removing column 'Jul. 31, 2010' </Log> |
| | <Log type="Info"> Process Flow-Through: Removing column 'Jul. 31, 2009' </Log> |
| | <Log type="Info"> Process Flow-Through: 105 - Statement - CONSOLIDATED STATEMENTS OF INCOME </Log> |
| | <Log type="Info"> Process Flow-Through: Removing column '3 Months Ended Jul. 31, 2012' </Log> |
| | <Log type="Info"> Process Flow-Through: Removing column '3 Months Ended Apr. 30, 2012' </Log> |
| | <Log type="Info"> Process Flow-Through: Removing column '3 Months Ended Jan. 31, 2012' </Log> |
| | <Log type="Info"> Process Flow-Through: Removing column '3 Months Ended Oct. 31, 2011' </Log> |
| | <Log type="Info"> Process Flow-Through: Removing column '3 Months Ended Jul. 31, 2011' </Log> |
| | <Log type="Info"> Process Flow-Through: Removing column '3 Months Ended Apr. 30, 2011' </Log> |
| | <Log type="Info"> Process Flow-Through: Removing column '3 Months Ended Jan. 31, 2011' </Log> |
| | <Log type="Info"> Process Flow-Through: Removing column '3 Months Ended Oct. 31, 2010' </Log> |
| | <Log type="Info"> Process Flow-Through: 106 - Statement - CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME </Log> |
| | <Log type="Info"> Process Flow-Through: 108 - Statement - CONSOLIDATED STATEMENTS OF EQUITY (Parenthetical) </Log> |
| | <Log type="Info"> Process Flow-Through: 109 - Statement - CONSOLIDATED STATEMENTS OF CASH FLOWS </Log> |
| | </Logs> |
| <InputFiles> |
| | <File> idt-20120731.xml </File> |
| | <File> idt-20120731.xsd </File> |
| | <File> idt-20120731_cal.xml </File> |
| | <File> idt-20120731_def.xml </File> |
| | <File> idt-20120731_lab.xml </File> |
| | <File> idt-20120731_pre.xml </File> |
| | </InputFiles> |
| <SupplementalFiles/> |
| <BaseTaxonomies/> |
| <HasPresentationLinkbase> true </HasPresentationLinkbase> |
| <HasCalculationLinkbase> true </HasCalculationLinkbase> |
| </FilingSummary> |