SEC Info  
    Home      Search      My Interests      Help      Sign In      Please Sign In

Idt Corp. – ‘10-K’ for 7/31/20 – ‘XML’

On:  Wednesday, 10/14/20, at 4:56pm ET   ·   For:  7/31/20   ·   Accession #:  1213900-20-31279   ·   File #:  1-16371

Previous ‘10-K’:  ‘10-K’ on 10/11/19 for 7/31/19   ·   Next:  ‘10-K/A’ on 12/22/20 for 7/31/20   ·   Latest:  ‘10-K’ on 10/16/23 for 7/31/23   ·   9 References:   

Find Words in Filings emoji
 
  in    Show  and   Hints

  As Of               Filer                 Filing    For·On·As Docs:Size             Issuer                      Filing Agent

10/14/20  Idt Corp.                         10-K        7/31/20  128:8.4M                                   EdgarAgents LLC/FA

Annual Report   —   Form 10-K
Filing Table of Contents

Document/Exhibit                   Description                      Pages   Size 

 1: 10-K        Annual Report                                       HTML   1.19M 
 2: EX-21.01    Subsidiaries of the Registrant                      HTML     38K 
 3: EX-23.01    Consent of Bdo Usa, LLP                             HTML     34K 
 4: EX-23.02    Consent of Grant Thornton, LLP                      HTML     34K 
 5: EX-31.01    Certification of Chief Executive Officer Pursuant   HTML     38K 
                to Section 302 of the Sarbanes-Oxley Act of 2002.                
 6: EX-31.02    Certification of Chief Financial Officer Pursuant   HTML     38K 
                to Section 302 of the Sarbanes-Oxley Act of 2002.                
 7: EX-32.01    Certification of Chief Executive Officer Pursuant   HTML     35K 
                to Section 906 of the Sarbanes-Oxley Act of 2002.                
 8: EX-32.02    Certification of Chief Financial Officer Pursuant   HTML     35K 
                to Section 906 of the Sarbanes-Oxley Act of 2002.                
15: R1          Document And Entity Information                     HTML     98K 
16: R2          Consolidated Balance Sheets                         HTML    149K 
17: R3          Consolidated Balance Sheets (Parentheticals)        HTML     57K 
18: R4          Consolidated Statements of Income                   HTML    115K 
19: R5          Consolidated Statements of Comprehensive Income     HTML     67K 
20: R6          Consolidated Statements of Equity                   HTML     92K 
21: R7          Consolidated Statements of Cash Flows               HTML    130K 
22: R8          Description of Business and Summary of Significant  HTML     81K 
                Accounting Policies                                              
23: R9          Revenue Recognition                                 HTML     79K 
24: R10         Leases                                              HTML     51K 
25: R11         Cash, Cash Equivalents, and Restricted Cash and     HTML     40K 
                Cash Equivalents                                                 
26: R12         Acquisitions                                        HTML     50K 
27: R13         Debt Securities                                     HTML     52K 
28: R14         Equity Investments                                  HTML     53K 
29: R15         Fair Value Measurements                             HTML     62K 
30: R16         Property, Plant and Equipment                       HTML     42K 
31: R17         Goodwill                                            HTML     41K 
32: R18         Other Intangible Assets                             HTML     45K 
33: R19         Other Operating Expense, Net                        HTML     43K 
34: R20         Note Payable and Revolving Credit Loan Payable      HTML     38K 
35: R21         Accrued Expenses                                    HTML     40K 
36: R22         Other (Expense) Income, Net                         HTML     40K 
37: R23         Income Taxes                                        HTML     69K 
38: R24         Equity                                              HTML     42K 
39: R25         Stock-Based Compensation                            HTML     57K 
40: R26         Accumulated Other Comprehensive Loss                HTML     45K 
41: R27         Commitments and Contingencies                       HTML     51K 
42: R28         Related Party Transactions                          HTML     45K 
43: R29         Defined Contribution Plans                          HTML     38K 
44: R30         Business Segment Information                        HTML     56K 
45: R31         Accounting Policies, by Policy (Policies)           HTML    143K 
46: R32         Description of Business and Summary of Significant  HTML     51K 
                Accounting Policies (Tables)                                     
47: R33         Revenue Recognition (Tables)                        HTML     62K 
48: R34         Leases (Tables)                                     HTML     58K 
49: R35         Cash, Cash Equivalents, and Restricted Cash and     HTML     38K 
                Cash Equivalents (Tables)                                        
50: R36         Acquisitions (Tables)                               HTML     51K 
51: R37         Debt Securities (Tables)                            HTML     53K 
52: R38         Equity Investments (Tables)                         HTML     53K 
53: R39         Fair Value Measurements (Tables)                    HTML     63K 
54: R40         Property, Plant and Equipment (Tables)              HTML     41K 
55: R41         Goodwill (Tables)                                   HTML     41K 
56: R42         Other Intangible Assets (Tables)                    HTML     45K 
57: R43         Other Operating Expense, Net (Tables)               HTML     41K 
58: R44         Accrued Expenses (Tables)                           HTML     40K 
59: R45         Other (Expense) Income, Net (Tables)                HTML     39K 
60: R46         Income Taxes (Tables)                               HTML     72K 
61: R47         Stock-Based Compensation (Tables)                   HTML     54K 
62: R48         Accumulated Other Comprehensive Loss (Tables)       HTML     44K 
63: R49         Business Segment Information (Tables)               HTML     53K 
64: R50         Description of Business and Summary of Significant  HTML     79K 
                Accounting Policies (Details)                                    
65: R51         Description of Business and Summary of Significant  HTML     48K 
                Accounting Policies (Details) - Schedule of                      
                weighted-average number of shares used in the                    
                calculation of basic and diluted earnings per                    
                share                                                            
66: R52         Description of Business and Summary of Significant  HTML     37K 
                Accounting Policies (Details) - Schedule of                      
                outstanding stock options excluded from the                      
                calculation of diluted earnings per share                        
67: R53         Description of Business and Summary of Significant  HTML     42K 
                Accounting Policies (Details) - Schedule of change               
                in the allowance for doubtful accounts                           
68: R54         Revenue Recognition (Details)                       HTML     40K 
69: R55         Revenue Recognition (Details) - Schedule of         HTML     62K 
                revenues disaggregated by business segment and                   
                service offered to customers                                     
70: R56         Revenue Recognition (Details) - Schedule of         HTML     66K 
                revenues disaggregated by geographic region                      
71: R57         Revenue Recognition (Details) - Schedule of         HTML     41K 
                deferred customer contract acquisition costs                     
72: R58         Leases (Details)                                    HTML     45K 
73: R59         Leases (Details) - Schedule of supplemental         HTML     45K 
                disclosures related to the Company's operating                   
                leases                                                           
74: R60         Leases (Details) - Schedule of supplemental         HTML     39K 
                disclosures related weighted average operating                   
                leases                                                           
75: R61         Leases (Details) - Schedule of aggregate operating  HTML     42K 
                lease liability                                                  
76: R62         Leases (Details) - Schedule of future minimum       HTML     54K 
                maturities of operating lease liabilities                        
77: R63         Leases (Details) - Schedule of future minimum       HTML     52K 
                payments for operating leases                                    
78: R64         Cash, Cash Equivalents, and Restricted Cash and     HTML     39K 
                Cash Equivalents (Details)                                       
79: R65         Cash, Cash Equivalents, and Restricted Cash and     HTML     44K 
                Cash Equivalents (Details) - Schedule of cash,                   
                cash equivalents, and restricted cash and cash                   
                equivalents                                                      
80: R66         Acquisitions (Details)                              HTML     43K 
81: R67         Acquisitions (Details) - Schedule of acquisition    HTML     42K 
                date fair value of consideration                                 
82: R68         Acquisitions (Details) - Schedule of impact of the  HTML     66K 
                acquisition's purchase price allocations on                      
                consolidated balance sheet                                       
83: R69         Acquisitions (Details) - Schedule of consolidated   HTML     66K 
                balance sheet and acquisition date fair value of                 
                total consideration transferred                                  
84: R70         Debt Securities (Details)                           HTML     39K 
85: R71         Debt Securities (Details) - Schedule of             HTML     56K 
                available-for-sale securities                                    
86: R72         Debt Securities (Details) - Schedule of             HTML     49K 
                contractual maturities of available-for-sale debt                
                securities                                                       
87: R73         Debt Securities (Details) - Schedule of             HTML     41K 
                available-for-sale securities, unrealized loss                   
                position                                                         
88: R74         Equity Investments (Details)                        HTML     62K 
89: R75         Equity Investments (Details) - Schedule of equity   HTML     53K 
                investments                                                      
90: R76         Equity Investments (Details) - Schedule of equity   HTML     41K 
                investments (Parentheticals)                                     
91: R77         Equity Investments (Details) - Schedule of          HTML     48K 
                carrying value of equity investments                             
92: R78         Equity Investments (Details) - Schedule of          HTML     40K 
                unrealized gains and losses for all equity                       
                investments                                                      
93: R79         Fair Value Measurements (Details)                   HTML     35K 
94: R80         Fair Value Measurements (Details) - Schedule of     HTML     57K 
                balance of assets measured at fair value on a                    
                recurring basis                                                  
95: R81         Fair Value Measurements (Details) - Schedule of     HTML     44K 
                assets measured at fair value on a recurring basis               
                using significant unobservable inputs (Level 3)                  
96: R82         Fair Value Measurements (Details) - Schedule of     HTML     44K 
                liabilities measured at fair value on a recurring                
                basis using significant unobservable inputs (Level               
                3)                                                               
97: R83         Property, Plant and Equipment (Details)             HTML     36K 
98: R84         Property, Plant and Equipment (Details) - Schedule  HTML     51K 
                of property, plant and equipment                                 
99: R85         Goodwill (Details) - Schedule of change in          HTML     48K 
                carrying amount of goodwill by operating segment                 
100: R86         Other Intangible Assets (Details)                   HTML     49K  
101: R87         Other Intangible Assets (Details) - Schedule of     HTML     54K  
                presents information on the Company's amortized                  
                intangible assets                                                
102: R88         Other Operating Expense, Net (Details)              HTML     39K  
103: R89         Other Operating Expense, Net (Details) - Schedule   HTML     48K  
                of other operating expense, net                                  
104: R90         Note Payable and Revolving Credit Loan Payable      HTML     45K  
                (Details)                                                        
105: R91         Accrued Expenses (Details) - Schedule of accrued    HTML     49K  
                expenses                                                         
106: R92         Other (Expense) Income, Net (Details) - Schedule    HTML     45K  
                of other (expense) income, net                                   
107: R93         Income Taxes (Details)                              HTML     63K  
108: R94         Income Taxes (Details) - Schedule of income before  HTML     44K  
                income taxes                                                     
109: R95         Income Taxes (Details) - Schedule of deferred       HTML     61K  
                income tax assets                                                
110: R96         Income Taxes (Details) - Schedule of benefit from   HTML     62K  
                (provision for) income taxes                                     
111: R97         Income Taxes (Details) - Schedule of U.S. federal   HTML     58K  
                statutory income tax rate and income taxes                       
                provided                                                         
112: R98         Income Taxes (Details) - Schedule of change in the  HTML     41K  
                valuation allowance                                              
113: R99         Equity (Details)                                    HTML     80K  
114: R100        Stock-Based Compensation (Details)                  HTML     83K  
115: R101        Stock-Based Compensation (Details) - Schedule of    HTML     68K  
                stock option activity                                            
116: R102        Stock-Based Compensation (Details) - Schedule of    HTML     56K  
                grants of restricted shares of Class B common                    
                stock                                                            
117: R103        Stock-Based Compensation (Details) - Schedule of    HTML     55K  
                grants of restricted shares                                      
118: R104        Accumulated Other Comprehensive Loss (Details) -    HTML     56K  
                Schedule of accumulated balances for each                        
                classification of other comprehensive loss                       
119: R105        Commitments and Contingencies (Details)             HTML     47K  
120: R106        Related Party Transactions (Details)                HTML     73K  
121: R107        Defined Contribution Plans (Details)                HTML     44K  
122: R108        Business Segment Information (Details)              HTML     36K  
123: R109        Business Segment Information (Details) - Schedule   HTML     62K  
                of operating results of business segments                        
124: R110        Business Segment Information (Details) - Schedule   HTML     46K  
                of net long-lived assets and total assets by                     
                geographic areas                                                 
126: XML         IDEA XML File -- Filing Summary                      XML    250K  
14: XML         XBRL Instance -- f10k2020_idtcorporation_htm         XML   1.65M 
125: EXCEL       IDEA Workbook of Financial Reports                  XLSX    152K  
10: EX-101.CAL  XBRL Calculations -- idt-20200731_cal                XML    214K 
11: EX-101.DEF  XBRL Definitions -- idt-20200731_def                 XML   1.16M 
12: EX-101.LAB  XBRL Labels -- idt-20200731_lab                      XML   2.12M 
13: EX-101.PRE  XBRL Presentations -- idt-20200731_pre               XML   1.15M 
 9: EX-101.SCH  XBRL Schema -- idt-20200731                          XSD    330K 
127: JSON        XBRL Instance as JSON Data -- MetaLinks              536±   778K  
128: ZIP         XBRL Zipped Folder -- 0001213900-20-031279-xbrl      Zip    311K  


‘XML’   —   IDEA XML File — Filing Summary


This Document is an IDEA XML File.


                                                                                                                                                                                
<?xml version="1.0" encoding="windows-1252"?>
<FilingSummary>
<Version> 3.20.2 </Version>
<ProcessingTime/>
<ReportFormat> html </ReportFormat>
<ContextCount> 273 </ContextCount>
<ElementCount> 561 </ElementCount>
<EntityCount> 1 </EntityCount>
<FootnotesReported> true </FootnotesReported>
<SegmentCount> 90 </SegmentCount>
<ScenarioCount> 0 </ScenarioCount>
<TuplesReported> false </TuplesReported>
<UnitCount> 4 </UnitCount>
<MyReports>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R1.htm </HtmlFileName>
<LongName> 000 - Document - Document And Entity Information </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/DocumentAndEntityInformation </Role>
<ShortName> Document And Entity Information </ShortName>
<MenuCategory> Cover </MenuCategory>
<Position> 1 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R2.htm </HtmlFileName>
<LongName> 001 - Statement - Consolidated Balance Sheets </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/ConsolidatedBalanceSheet </Role>
<ShortName> Consolidated Balance Sheets </ShortName>
<MenuCategory> Statements </MenuCategory>
<Position> 2 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R3.htm </HtmlFileName>
<LongName> 002 - Statement - Consolidated Balance Sheets (Parentheticals) </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/ConsolidatedBalanceSheet_Parentheticals </Role>
<ShortName> Consolidated Balance Sheets (Parentheticals) </ShortName>
<MenuCategory> Statements </MenuCategory>
<Position> 3 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R4.htm </HtmlFileName>
<LongName> 003 - Statement - Consolidated Statements of Income </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/ConsolidatedIncomeStatement </Role>
<ShortName> Consolidated Statements of Income </ShortName>
<MenuCategory> Statements </MenuCategory>
<Position> 4 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R5.htm </HtmlFileName>
<LongName> 004 - Statement - Consolidated Statements of Comprehensive Income </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/ConsolidatedBalanceSheet0 </Role>
<ShortName> Consolidated Statements of Comprehensive Income </ShortName>
<MenuCategory> Statements </MenuCategory>
<Position> 5 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R6.htm </HtmlFileName>
<LongName> 005 - Statement - Consolidated Statements of Equity </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/ShareholdersEquityType2or3 </Role>
<ShortName> Consolidated Statements of Equity </ShortName>
<MenuCategory> Statements </MenuCategory>
<Position> 6 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R7.htm </HtmlFileName>
<LongName> 006 - Statement - Consolidated Statements of Cash Flows </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/ConsolidatedCashFlow </Role>
<ShortName> Consolidated Statements of Cash Flows </ShortName>
<MenuCategory> Statements </MenuCategory>
<Position> 7 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R8.htm </HtmlFileName>
<LongName> 007 - Disclosure - Description of Business and Summary of Significant Accounting Policies </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/DescriptionofBusinessandSummaryofSignificantAccountingPolicies </Role>
<ShortName> Description of Business and Summary of Significant Accounting Policies </ShortName>
<MenuCategory> Notes </MenuCategory>
<Position> 8 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R9.htm </HtmlFileName>
<LongName> 008 - Disclosure - Revenue Recognition </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/RevenueRecognition </Role>
<ShortName> Revenue Recognition </ShortName>
<MenuCategory> Notes </MenuCategory>
<Position> 9 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R10.htm </HtmlFileName>
<LongName> 009 - Disclosure - Leases </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/Leases </Role>
<ShortName> Leases </ShortName>
<MenuCategory> Notes </MenuCategory>
<Position> 10 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R11.htm </HtmlFileName>
<LongName> 010 - Disclosure - Cash, Cash Equivalents, and Restricted Cash and Cash Equivalents </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/CashCashEquivalentsandRestrictedCashandCashEquivalents </Role>
<ShortName> Cash, Cash Equivalents, and Restricted Cash and Cash Equivalents </ShortName>
<MenuCategory> Notes </MenuCategory>
<Position> 11 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R12.htm </HtmlFileName>
<LongName> 011 - Disclosure - Acquisitions </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/Acquisitions </Role>
<ShortName> Acquisitions </ShortName>
<MenuCategory> Notes </MenuCategory>
<Position> 12 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R13.htm </HtmlFileName>
<LongName> 012 - Disclosure - Debt Securities </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/DebtSecurities </Role>
<ShortName> Debt Securities </ShortName>
<MenuCategory> Notes </MenuCategory>
<Position> 13 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R14.htm </HtmlFileName>
<LongName> 013 - Disclosure - Equity Investments </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/EquityInvestments </Role>
<ShortName> Equity Investments </ShortName>
<MenuCategory> Notes </MenuCategory>
<Position> 14 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R15.htm </HtmlFileName>
<LongName> 014 - Disclosure - Fair Value Measurements </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/FairValueMeasurements </Role>
<ShortName> Fair Value Measurements </ShortName>
<MenuCategory> Notes </MenuCategory>
<Position> 15 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R16.htm </HtmlFileName>
<LongName> 015 - Disclosure - Property, Plant and Equipment </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/PropertyPlantandEquipment </Role>
<ShortName> Property, Plant and Equipment </ShortName>
<MenuCategory> Notes </MenuCategory>
<Position> 16 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R17.htm </HtmlFileName>
<LongName> 016 - Disclosure - Goodwill </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/Goodwill </Role>
<ShortName> Goodwill </ShortName>
<MenuCategory> Notes </MenuCategory>
<Position> 17 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R18.htm </HtmlFileName>
<LongName> 017 - Disclosure - Other Intangible Assets </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/OtherIntangibleAssets </Role>
<ShortName> Other Intangible Assets </ShortName>
<MenuCategory> Notes </MenuCategory>
<Position> 18 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R19.htm </HtmlFileName>
<LongName> 018 - Disclosure - Other Operating Expense, Net </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/OtherOperatingExpenseNet </Role>
<ShortName> Other Operating Expense, Net </ShortName>
<MenuCategory> Notes </MenuCategory>
<Position> 19 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R20.htm </HtmlFileName>
<LongName> 019 - Disclosure - Note Payable and Revolving Credit Loan Payable </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/NotePayableandRevolvingCreditLoanPayable </Role>
<ShortName> Note Payable and Revolving Credit Loan Payable </ShortName>
<MenuCategory> Notes </MenuCategory>
<Position> 20 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R21.htm </HtmlFileName>
<LongName> 020 - Disclosure - Accrued Expenses </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/AccruedExpenses </Role>
<ShortName> Accrued Expenses </ShortName>
<MenuCategory> Notes </MenuCategory>
<Position> 21 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R22.htm </HtmlFileName>
<LongName> 021 - Disclosure - Other (Expense) Income, Net </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/OtherExpenseIncomeNet </Role>
<ShortName> Other (Expense) Income, Net </ShortName>
<MenuCategory> Notes </MenuCategory>
<Position> 22 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R23.htm </HtmlFileName>
<LongName> 022 - Disclosure - Income Taxes </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/IncomeTaxes </Role>
<ShortName> Income Taxes </ShortName>
<MenuCategory> Notes </MenuCategory>
<Position> 23 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R24.htm </HtmlFileName>
<LongName> 023 - Disclosure - Equity </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/Equity </Role>
<ShortName> Equity </ShortName>
<MenuCategory> Notes </MenuCategory>
<Position> 24 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R25.htm </HtmlFileName>
<LongName> 024 - Disclosure - Stock-Based Compensation </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/StockBasedCompensation </Role>
<ShortName> Stock-Based Compensation </ShortName>
<MenuCategory> Notes </MenuCategory>
<Position> 25 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R26.htm </HtmlFileName>
<LongName> 025 - Disclosure - Accumulated Other Comprehensive Loss </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/AccumulatedOtherComprehensiveLoss </Role>
<ShortName> Accumulated Other Comprehensive Loss </ShortName>
<MenuCategory> Notes </MenuCategory>
<Position> 26 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R27.htm </HtmlFileName>
<LongName> 026 - Disclosure - Commitments and Contingencies </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/CommitmentsandContingencies </Role>
<ShortName> Commitments and Contingencies </ShortName>
<MenuCategory> Notes </MenuCategory>
<Position> 27 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R28.htm </HtmlFileName>
<LongName> 027 - Disclosure - Related Party Transactions </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/RelatedPartyTransactions </Role>
<ShortName> Related Party Transactions </ShortName>
<MenuCategory> Notes </MenuCategory>
<Position> 28 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R29.htm </HtmlFileName>
<LongName> 028 - Disclosure - Defined Contribution Plans </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/DefinedContributionPlans </Role>
<ShortName> Defined Contribution Plans </ShortName>
<MenuCategory> Notes </MenuCategory>
<Position> 29 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R30.htm </HtmlFileName>
<LongName> 029 - Disclosure - Business Segment Information </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/BusinessSegmentInformation </Role>
<ShortName> Business Segment Information </ShortName>
<MenuCategory> Notes </MenuCategory>
<Position> 30 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R31.htm </HtmlFileName>
<LongName> 030 - Disclosure - Accounting Policies, by Policy (Policies) </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/AccountingPoliciesByPolicy </Role>
<ShortName> Accounting Policies, by Policy (Policies) </ShortName>
<MenuCategory> Policies </MenuCategory>
<ParentRole> http://www.www.idt.net/role/DescriptionofBusinessandSummaryofSignificantAccountingPolicies </ParentRole>
<Position> 31 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R32.htm </HtmlFileName>
<LongName> 031 - Disclosure - Description of Business and Summary of Significant Accounting Policies (Tables) </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesTables </Role>
<ShortName> Description of Business and Summary of Significant Accounting Policies (Tables) </ShortName>
<MenuCategory> Tables </MenuCategory>
<ParentRole> http://www.www.idt.net/role/DescriptionofBusinessandSummaryofSignificantAccountingPolicies </ParentRole>
<Position> 32 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R33.htm </HtmlFileName>
<LongName> 032 - Disclosure - Revenue Recognition (Tables) </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/RevenueRecognitionTables </Role>
<ShortName> Revenue Recognition (Tables) </ShortName>
<MenuCategory> Tables </MenuCategory>
<ParentRole> http://www.www.idt.net/role/RevenueRecognition </ParentRole>
<Position> 33 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R34.htm </HtmlFileName>
<LongName> 033 - Disclosure - Leases (Tables) </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/LeasesTables </Role>
<ShortName> Leases (Tables) </ShortName>
<MenuCategory> Tables </MenuCategory>
<ParentRole> http://www.www.idt.net/role/Leases </ParentRole>
<Position> 34 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R35.htm </HtmlFileName>
<LongName> 034 - Disclosure - Cash, Cash Equivalents, and Restricted Cash and Cash Equivalents (Tables) </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/CashCashEquivalentsandRestrictedCashandCashEquivalentsTables </Role>
<ShortName> Cash, Cash Equivalents, and Restricted Cash and Cash Equivalents (Tables) </ShortName>
<MenuCategory> Tables </MenuCategory>
<ParentRole> http://www.www.idt.net/role/CashCashEquivalentsandRestrictedCashandCashEquivalents </ParentRole>
<Position> 35 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R36.htm </HtmlFileName>
<LongName> 035 - Disclosure - Acquisitions (Tables) </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/AcquisitionsTables </Role>
<ShortName> Acquisitions (Tables) </ShortName>
<MenuCategory> Tables </MenuCategory>
<ParentRole> http://www.www.idt.net/role/Acquisitions </ParentRole>
<Position> 36 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R37.htm </HtmlFileName>
<LongName> 036 - Disclosure - Debt Securities (Tables) </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/DebtSecuritiesTables </Role>
<ShortName> Debt Securities (Tables) </ShortName>
<MenuCategory> Tables </MenuCategory>
<ParentRole> http://www.www.idt.net/role/DebtSecurities </ParentRole>
<Position> 37 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R38.htm </HtmlFileName>
<LongName> 037 - Disclosure - Equity Investments (Tables) </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/EquityInvestmentsTables </Role>
<ShortName> Equity Investments (Tables) </ShortName>
<MenuCategory> Tables </MenuCategory>
<ParentRole> http://www.www.idt.net/role/EquityInvestments </ParentRole>
<Position> 38 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R39.htm </HtmlFileName>
<LongName> 038 - Disclosure - Fair Value Measurements (Tables) </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/FairValueMeasurementsTables </Role>
<ShortName> Fair Value Measurements (Tables) </ShortName>
<MenuCategory> Tables </MenuCategory>
<ParentRole> http://www.www.idt.net/role/FairValueMeasurements </ParentRole>
<Position> 39 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R40.htm </HtmlFileName>
<LongName> 039 - Disclosure - Property, Plant and Equipment (Tables) </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/PropertyPlantandEquipmentTables </Role>
<ShortName> Property, Plant and Equipment (Tables) </ShortName>
<MenuCategory> Tables </MenuCategory>
<ParentRole> http://www.www.idt.net/role/PropertyPlantandEquipment </ParentRole>
<Position> 40 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R41.htm </HtmlFileName>
<LongName> 040 - Disclosure - Goodwill (Tables) </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/GoodwillTables </Role>
<ShortName> Goodwill (Tables) </ShortName>
<MenuCategory> Tables </MenuCategory>
<ParentRole> http://www.www.idt.net/role/Goodwill </ParentRole>
<Position> 41 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R42.htm </HtmlFileName>
<LongName> 041 - Disclosure - Other Intangible Assets (Tables) </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/OtherIntangibleAssetsTables </Role>
<ShortName> Other Intangible Assets (Tables) </ShortName>
<MenuCategory> Tables </MenuCategory>
<ParentRole> http://www.www.idt.net/role/OtherIntangibleAssets </ParentRole>
<Position> 42 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R43.htm </HtmlFileName>
<LongName> 042 - Disclosure - Other Operating Expense, Net (Tables) </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/OtherOperatingExpenseNetTables </Role>
<ShortName> Other Operating Expense, Net (Tables) </ShortName>
<MenuCategory> Tables </MenuCategory>
<ParentRole> http://www.www.idt.net/role/OtherOperatingExpenseNet </ParentRole>
<Position> 43 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R44.htm </HtmlFileName>
<LongName> 043 - Disclosure - Accrued Expenses (Tables) </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/AccruedExpensesTables </Role>
<ShortName> Accrued Expenses (Tables) </ShortName>
<MenuCategory> Tables </MenuCategory>
<ParentRole> http://www.www.idt.net/role/AccruedExpenses </ParentRole>
<Position> 44 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R45.htm </HtmlFileName>
<LongName> 044 - Disclosure - Other (Expense) Income, Net (Tables) </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/OtherExpenseIncomeNetTables </Role>
<ShortName> Other (Expense) Income, Net (Tables) </ShortName>
<MenuCategory> Tables </MenuCategory>
<ParentRole> http://www.www.idt.net/role/OtherIntangibleAssets </ParentRole>
<Position> 45 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R46.htm </HtmlFileName>
<LongName> 045 - Disclosure - Income Taxes (Tables) </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/IncomeTaxesTables </Role>
<ShortName> Income Taxes (Tables) </ShortName>
<MenuCategory> Tables </MenuCategory>
<ParentRole> http://www.www.idt.net/role/IncomeTaxes </ParentRole>
<Position> 46 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R47.htm </HtmlFileName>
<LongName> 046 - Disclosure - Stock-Based Compensation (Tables) </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/StockBasedCompensationTables </Role>
<ShortName> Stock-Based Compensation (Tables) </ShortName>
<MenuCategory> Tables </MenuCategory>
<ParentRole> http://www.www.idt.net/role/StockBasedCompensation </ParentRole>
<Position> 47 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R48.htm </HtmlFileName>
<LongName> 047 - Disclosure - Accumulated Other Comprehensive Loss (Tables) </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/AccumulatedOtherComprehensiveLossTables </Role>
<ShortName> Accumulated Other Comprehensive Loss (Tables) </ShortName>
<MenuCategory> Tables </MenuCategory>
<ParentRole> http://www.www.idt.net/role/AccumulatedOtherComprehensiveLoss </ParentRole>
<Position> 48 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R49.htm </HtmlFileName>
<LongName> 048 - Disclosure - Business Segment Information (Tables) </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/BusinessSegmentInformationTables </Role>
<ShortName> Business Segment Information (Tables) </ShortName>
<MenuCategory> Tables </MenuCategory>
<ParentRole> http://www.www.idt.net/role/BusinessSegmentInformation </ParentRole>
<Position> 49 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R50.htm </HtmlFileName>
<LongName> 049 - Disclosure - Description of Business and Summary of Significant Accounting Policies (Details) </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesDetails </Role>
<ShortName> Description of Business and Summary of Significant Accounting Policies (Details) </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesTables </ParentRole>
<Position> 50 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R51.htm </HtmlFileName>
<LongName> 050 - Disclosure - Description of Business and Summary of Significant Accounting Policies (Details) - Schedule of weighted-average number of shares used in the calculation of basic and diluted earnings per share </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/ScheduleofweightedaveragenumberofsharesusedinthecalculationofbasicanddilutedearningspershareTable </Role>
<ShortName> Description of Business and Summary of Significant Accounting Policies (Details) - Schedule of weighted-average number of shares used in the calculation of basic and diluted earnings per share </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesTables </ParentRole>
<Position> 51 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R52.htm </HtmlFileName>
<LongName> 051 - Disclosure - Description of Business and Summary of Significant Accounting Policies (Details) - Schedule of outstanding stock options excluded from the calculation of diluted earnings per share </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/ScheduleofoutstandingstockoptionsexcludedfromthecalculationofdilutedearningspershareTable </Role>
<ShortName> Description of Business and Summary of Significant Accounting Policies (Details) - Schedule of outstanding stock options excluded from the calculation of diluted earnings per share </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesTables </ParentRole>
<Position> 52 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R53.htm </HtmlFileName>
<LongName> 052 - Disclosure - Description of Business and Summary of Significant Accounting Policies (Details) - Schedule of change in the allowance for doubtful accounts </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/ScheduleofchangeintheallowancefordoubtfulaccountsTable </Role>
<ShortName> Description of Business and Summary of Significant Accounting Policies (Details) - Schedule of change in the allowance for doubtful accounts </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/DescriptionofBusinessandSummaryofSignificantAccountingPoliciesTables </ParentRole>
<Position> 53 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R54.htm </HtmlFileName>
<LongName> 053 - Disclosure - Revenue Recognition (Details) </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/RevenueRecognitionDetails </Role>
<ShortName> Revenue Recognition (Details) </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/RevenueRecognitionTables </ParentRole>
<Position> 54 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R55.htm </HtmlFileName>
<LongName> 054 - Disclosure - Revenue Recognition (Details) - Schedule of revenues disaggregated by business segment and service offered to customers </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/ScheduleofrevenuesdisaggregatedbybusinesssegmentandserviceofferedtocustomersTable </Role>
<ShortName> Revenue Recognition (Details) - Schedule of revenues disaggregated by business segment and service offered to customers </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/RevenueRecognitionTables </ParentRole>
<Position> 55 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R56.htm </HtmlFileName>
<LongName> 055 - Disclosure - Revenue Recognition (Details) - Schedule of revenues disaggregated by geographic region </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/ScheduleofrevenuesdisaggregatedbygeographicregionTable </Role>
<ShortName> Revenue Recognition (Details) - Schedule of revenues disaggregated by geographic region </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/RevenueRecognitionTables </ParentRole>
<Position> 56 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R57.htm </HtmlFileName>
<LongName> 056 - Disclosure - Revenue Recognition (Details) - Schedule of deferred customer contract acquisition costs </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/ScheduleofdeferredcustomercontractacquisitioncostsTable </Role>
<ShortName> Revenue Recognition (Details) - Schedule of deferred customer contract acquisition costs </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/RevenueRecognitionTables </ParentRole>
<Position> 57 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R58.htm </HtmlFileName>
<LongName> 057 - Disclosure - Leases (Details) </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/LeasesDetails </Role>
<ShortName> Leases (Details) </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/LeasesTables </ParentRole>
<Position> 58 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R59.htm </HtmlFileName>
<LongName> 058 - Disclosure - Leases (Details) - Schedule of supplemental disclosures related to the Company's operating leases </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/ScheduleofsupplementaldisclosuresrelatedtotheCompanysoperatingleasesTable </Role>
<ShortName> Leases (Details) - Schedule of supplemental disclosures related to the Company's operating leases </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/LeasesTables </ParentRole>
<Position> 59 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R60.htm </HtmlFileName>
<LongName> 059 - Disclosure - Leases (Details) - Schedule of supplemental disclosures related weighted average operating leases </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/ScheduleofsupplementaldisclosuresrelatedweightedaverageoperatingleasesTable </Role>
<ShortName> Leases (Details) - Schedule of supplemental disclosures related weighted average operating leases </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/LeasesTables </ParentRole>
<Position> 60 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R61.htm </HtmlFileName>
<LongName> 060 - Disclosure - Leases (Details) - Schedule of aggregate operating lease liability </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/ScheduleofaggregateoperatingleaseliabilityTable </Role>
<ShortName> Leases (Details) - Schedule of aggregate operating lease liability </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/LeasesTables </ParentRole>
<Position> 61 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R62.htm </HtmlFileName>
<LongName> 061 - Disclosure - Leases (Details) - Schedule of future minimum maturities of operating lease liabilities </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/ScheduleoffutureminimummaturitiesofoperatingleaseliabilitiesTable </Role>
<ShortName> Leases (Details) - Schedule of future minimum maturities of operating lease liabilities </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/LeasesTables </ParentRole>
<Position> 62 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R63.htm </HtmlFileName>
<LongName> 062 - Disclosure - Leases (Details) - Schedule of future minimum payments for operating leases </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/ScheduleoffutureminimumpaymentsforoperatingleasesTable </Role>
<ShortName> Leases (Details) - Schedule of future minimum payments for operating leases </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/LeasesTables </ParentRole>
<Position> 63 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R64.htm </HtmlFileName>
<LongName> 063 - Disclosure - Cash, Cash Equivalents, and Restricted Cash and Cash Equivalents (Details) </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/CashCashEquivalentsandRestrictedCashandCashEquivalentsDetails </Role>
<ShortName> Cash, Cash Equivalents, and Restricted Cash and Cash Equivalents (Details) </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/CashCashEquivalentsandRestrictedCashandCashEquivalentsTables </ParentRole>
<Position> 64 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R65.htm </HtmlFileName>
<LongName> 064 - Disclosure - Cash, Cash Equivalents, and Restricted Cash and Cash Equivalents (Details) - Schedule of cash, cash equivalents, and restricted cash and cash equivalents </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/ScheduleofcashcashequivalentsandrestrictedcashandcashequivalentsTable </Role>
<ShortName> Cash, Cash Equivalents, and Restricted Cash and Cash Equivalents (Details) - Schedule of cash, cash equivalents, and restricted cash and cash equivalents </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/CashCashEquivalentsandRestrictedCashandCashEquivalentsTables </ParentRole>
<Position> 65 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R66.htm </HtmlFileName>
<LongName> 065 - Disclosure - Acquisitions (Details) </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/AcquisitionsDetails </Role>
<ShortName> Acquisitions (Details) </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/AcquisitionsTables </ParentRole>
<Position> 66 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R67.htm </HtmlFileName>
<LongName> 066 - Disclosure - Acquisitions (Details) - Schedule of acquisition date fair value of consideration </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/ScheduleofacquisitiondatefairvalueofconsiderationTable </Role>
<ShortName> Acquisitions (Details) - Schedule of acquisition date fair value of consideration </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/AcquisitionsTables </ParentRole>
<Position> 67 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R68.htm </HtmlFileName>
<LongName> 067 - Disclosure - Acquisitions (Details) - Schedule of impact of the acquisition's purchase price allocations on consolidated balance sheet </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/ScheduleofimpactoftheacquisitionspurchasepriceallocationsonconsolidatedbalancesheetTable </Role>
<ShortName> Acquisitions (Details) - Schedule of impact of the acquisition's purchase price allocations on consolidated balance sheet </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/AcquisitionsTables </ParentRole>
<Position> 68 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R69.htm </HtmlFileName>
<LongName> 068 - Disclosure - Acquisitions (Details) - Schedule of consolidated balance sheet and acquisition date fair value of total consideration transferred </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/ScheduleofconsolidatedbalancesheetandacquisitiondatefairvalueoftotalconsiderationtransferredTable </Role>
<ShortName> Acquisitions (Details) - Schedule of consolidated balance sheet and acquisition date fair value of total consideration transferred </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/AcquisitionsTables </ParentRole>
<Position> 69 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R70.htm </HtmlFileName>
<LongName> 069 - Disclosure - Debt Securities (Details) </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/DebtSecuritiesDetails </Role>
<ShortName> Debt Securities (Details) </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/DebtSecuritiesTables </ParentRole>
<Position> 70 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R71.htm </HtmlFileName>
<LongName> 070 - Disclosure - Debt Securities (Details) - Schedule of available-for-sale securities </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/ScheduleofavailableforsalesecuritiesTable </Role>
<ShortName> Debt Securities (Details) - Schedule of available-for-sale securities </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/DebtSecuritiesTables </ParentRole>
<Position> 71 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R72.htm </HtmlFileName>
<LongName> 071 - Disclosure - Debt Securities (Details) - Schedule of contractual maturities of available-for-sale debt securities </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/ScheduleofcontractualmaturitiesofavailableforsaledebtsecuritiesTable </Role>
<ShortName> Debt Securities (Details) - Schedule of contractual maturities of available-for-sale debt securities </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/DebtSecuritiesTables </ParentRole>
<Position> 72 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R73.htm </HtmlFileName>
<LongName> 072 - Disclosure - Debt Securities (Details) - Schedule of available-for-sale securities, unrealized loss position </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/ScheduleofavailableforsalesecuritiesunrealizedlosspositionTable </Role>
<ShortName> Debt Securities (Details) - Schedule of available-for-sale securities, unrealized loss position </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/DebtSecuritiesTables </ParentRole>
<Position> 73 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R74.htm </HtmlFileName>
<LongName> 073 - Disclosure - Equity Investments (Details) </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/EquityInvestmentsDetails </Role>
<ShortName> Equity Investments (Details) </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/EquityInvestmentsTables </ParentRole>
<Position> 74 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R75.htm </HtmlFileName>
<LongName> 074 - Disclosure - Equity Investments (Details) - Schedule of equity investments </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/ScheduleofequityinvestmentsTable </Role>
<ShortName> Equity Investments (Details) - Schedule of equity investments </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/EquityInvestmentsTables </ParentRole>
<Position> 75 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R76.htm </HtmlFileName>
<LongName> 075 - Disclosure - Equity Investments (Details) - Schedule of equity investments (Parentheticals) </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/ScheduleofequityinvestmentsTable_Parentheticals </Role>
<ShortName> Equity Investments (Details) - Schedule of equity investments (Parentheticals) </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/EquityInvestmentsTables </ParentRole>
<Position> 76 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R77.htm </HtmlFileName>
<LongName> 076 - Disclosure - Equity Investments (Details) - Schedule of carrying value of equity investments </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/ScheduleofcarryingvalueofequityinvestmentsTable </Role>
<ShortName> Equity Investments (Details) - Schedule of carrying value of equity investments </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/EquityInvestmentsTables </ParentRole>
<Position> 77 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R78.htm </HtmlFileName>
<LongName> 077 - Disclosure - Equity Investments (Details) - Schedule of unrealized gains and losses for all equity investments </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/ScheduleofunrealizedgainsandlossesforallequityinvestmentsTable </Role>
<ShortName> Equity Investments (Details) - Schedule of unrealized gains and losses for all equity investments </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/EquityInvestmentsTables </ParentRole>
<Position> 78 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R79.htm </HtmlFileName>
<LongName> 078 - Disclosure - Fair Value Measurements (Details) </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/FairValueMeasurementsDetails </Role>
<ShortName> Fair Value Measurements (Details) </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/FairValueMeasurementsTables </ParentRole>
<Position> 79 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R80.htm </HtmlFileName>
<LongName> 079 - Disclosure - Fair Value Measurements (Details) - Schedule of balance of assets measured at fair value on a recurring basis </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/ScheduleofbalanceofassetsmeasuredatfairvalueonarecurringbasisTable </Role>
<ShortName> Fair Value Measurements (Details) - Schedule of balance of assets measured at fair value on a recurring basis </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/FairValueMeasurementsTables </ParentRole>
<Position> 80 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R81.htm </HtmlFileName>
<LongName> 080 - Disclosure - Fair Value Measurements (Details) - Schedule of assets measured at fair value on a recurring basis using significant unobservable inputs (Level 3) </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/ScheduleofassetsmeasuredatfairvalueonarecurringbasisusingsignificantunobservableinputsLevel3Table </Role>
<ShortName> Fair Value Measurements (Details) - Schedule of assets measured at fair value on a recurring basis using significant unobservable inputs (Level 3) </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/FairValueMeasurementsTables </ParentRole>
<Position> 81 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R82.htm </HtmlFileName>
<LongName> 081 - Disclosure - Fair Value Measurements (Details) - Schedule of liabilities measured at fair value on a recurring basis using significant unobservable inputs (Level 3) </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/ScheduleofliabilitiesmeasuredatfairvalueonarecurringbasisusingsignificantunobservableinputsLevel3Table </Role>
<ShortName> Fair Value Measurements (Details) - Schedule of liabilities measured at fair value on a recurring basis using significant unobservable inputs (Level 3) </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/FairValueMeasurementsTables </ParentRole>
<Position> 82 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R83.htm </HtmlFileName>
<LongName> 082 - Disclosure - Property, Plant and Equipment (Details) </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/PropertyPlantandEquipmentDetails </Role>
<ShortName> Property, Plant and Equipment (Details) </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/PropertyPlantandEquipmentTables </ParentRole>
<Position> 83 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R84.htm </HtmlFileName>
<LongName> 083 - Disclosure - Property, Plant and Equipment (Details) - Schedule of property, plant and equipment </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/ScheduleofpropertyplantandequipmentTable </Role>
<ShortName> Property, Plant and Equipment (Details) - Schedule of property, plant and equipment </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/PropertyPlantandEquipmentTables </ParentRole>
<Position> 84 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R85.htm </HtmlFileName>
<LongName> 084 - Disclosure - Goodwill (Details) - Schedule of change in carrying amount of goodwill by operating segment </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/ScheduleofchangeincarryingamountofgoodwillbyoperatingsegmentTable </Role>
<ShortName> Goodwill (Details) - Schedule of change in carrying amount of goodwill by operating segment </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/GoodwillTables </ParentRole>
<Position> 85 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R86.htm </HtmlFileName>
<LongName> 085 - Disclosure - Other Intangible Assets (Details) </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/OtherIntangibleAssetsDetails </Role>
<ShortName> Other Intangible Assets (Details) </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/OtherIntangibleAssetsTables </ParentRole>
<Position> 86 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R87.htm </HtmlFileName>
<LongName> 086 - Disclosure - Other Intangible Assets (Details) - Schedule of presents information on the Company's amortized intangible assets </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/ScheduleofpresentsinformationontheCompanysamortizedintangibleassetsTable </Role>
<ShortName> Other Intangible Assets (Details) - Schedule of presents information on the Company's amortized intangible assets </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/OtherIntangibleAssetsTables </ParentRole>
<Position> 87 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R88.htm </HtmlFileName>
<LongName> 087 - Disclosure - Other Operating Expense, Net (Details) </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/OtherOperatingExpenseNetDetails </Role>
<ShortName> Other Operating Expense, Net (Details) </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/OtherOperatingExpenseNetTables </ParentRole>
<Position> 88 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R89.htm </HtmlFileName>
<LongName> 088 - Disclosure - Other Operating Expense, Net (Details) - Schedule of other operating expense, net </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/ScheduleofotheroperatingexpensenetTable </Role>
<ShortName> Other Operating Expense, Net (Details) - Schedule of other operating expense, net </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/OtherOperatingExpenseNetTables </ParentRole>
<Position> 89 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R90.htm </HtmlFileName>
<LongName> 089 - Disclosure - Note Payable and Revolving Credit Loan Payable (Details) </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/NotePayableandRevolvingCreditLoanPayableDetails </Role>
<ShortName> Note Payable and Revolving Credit Loan Payable (Details) </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/NotePayableandRevolvingCreditLoanPayable </ParentRole>
<Position> 90 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R91.htm </HtmlFileName>
<LongName> 090 - Disclosure - Accrued Expenses (Details) - Schedule of accrued expenses </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/ScheduleofaccruedexpensesTable </Role>
<ShortName> Accrued Expenses (Details) - Schedule of accrued expenses </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/AccruedExpensesTables </ParentRole>
<Position> 91 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R92.htm </HtmlFileName>
<LongName> 091 - Disclosure - Other (Expense) Income, Net (Details) - Schedule of other (expense) income, net </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/ScheduleofotherexpenseincomenetTable </Role>
<ShortName> Other (Expense) Income, Net (Details) - Schedule of other (expense) income, net </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/OtherIntangibleAssetsTables </ParentRole>
<Position> 92 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R93.htm </HtmlFileName>
<LongName> 092 - Disclosure - Income Taxes (Details) </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/IncomeTaxesDetails </Role>
<ShortName> Income Taxes (Details) </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/IncomeTaxesTables </ParentRole>
<Position> 93 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R94.htm </HtmlFileName>
<LongName> 093 - Disclosure - Income Taxes (Details) - Schedule of income before income taxes </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/ScheduleofincomebeforeincometaxesTable </Role>
<ShortName> Income Taxes (Details) - Schedule of income before income taxes </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/IncomeTaxesTables </ParentRole>
<Position> 94 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R95.htm </HtmlFileName>
<LongName> 094 - Disclosure - Income Taxes (Details) - Schedule of deferred income tax assets </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/ScheduleofdeferredincometaxassetsTable </Role>
<ShortName> Income Taxes (Details) - Schedule of deferred income tax assets </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/IncomeTaxesTables </ParentRole>
<Position> 95 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R96.htm </HtmlFileName>
<LongName> 095 - Disclosure - Income Taxes (Details) - Schedule of benefit from (provision for) income taxes </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/ScheduleofbenefitfromprovisionforincometaxesTable </Role>
<ShortName> Income Taxes (Details) - Schedule of benefit from (provision for) income taxes </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/IncomeTaxesTables </ParentRole>
<Position> 96 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R97.htm </HtmlFileName>
<LongName> 096 - Disclosure - Income Taxes (Details) - Schedule of U.S. federal statutory income tax rate and income taxes provided </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/ScheduleofUSfederalstatutoryincometaxrateandincometaxesprovidedTable </Role>
<ShortName> Income Taxes (Details) - Schedule of U.S. federal statutory income tax rate and income taxes provided </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/IncomeTaxesTables </ParentRole>
<Position> 97 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R98.htm </HtmlFileName>
<LongName> 097 - Disclosure - Income Taxes (Details) - Schedule of change in the valuation allowance </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/ScheduleofchangeinthevaluationallowanceTable </Role>
<ShortName> Income Taxes (Details) - Schedule of change in the valuation allowance </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/IncomeTaxesTables </ParentRole>
<Position> 98 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R99.htm </HtmlFileName>
<LongName> 098 - Disclosure - Equity (Details) </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/EquityDetails </Role>
<ShortName> Equity (Details) </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/EquityInvestmentsTables </ParentRole>
<Position> 99 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R100.htm </HtmlFileName>
<LongName> 099 - Disclosure - Stock-Based Compensation (Details) </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/StockBasedCompensationDetails </Role>
<ShortName> Stock-Based Compensation (Details) </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/StockBasedCompensationTables </ParentRole>
<Position> 100 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R101.htm </HtmlFileName>
<LongName> 100 - Disclosure - Stock-Based Compensation (Details) - Schedule of stock option activity </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/ScheduleofstockoptionactivityTable </Role>
<ShortName> Stock-Based Compensation (Details) - Schedule of stock option activity </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/StockBasedCompensationTables </ParentRole>
<Position> 101 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R102.htm </HtmlFileName>
<LongName> 101 - Disclosure - Stock-Based Compensation (Details) - Schedule of grants of restricted shares of Class B common stock </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/ScheduleofgrantsofrestrictedsharesofClassBcommonstockTable </Role>
<ShortName> Stock-Based Compensation (Details) - Schedule of grants of restricted shares of Class B common stock </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/StockBasedCompensationTables </ParentRole>
<Position> 102 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R103.htm </HtmlFileName>
<LongName> 102 - Disclosure - Stock-Based Compensation (Details) - Schedule of grants of restricted shares </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/ScheduleofgrantsofrestrictedsharesTable </Role>
<ShortName> Stock-Based Compensation (Details) - Schedule of grants of restricted shares </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/StockBasedCompensationTables </ParentRole>
<Position> 103 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R104.htm </HtmlFileName>
<LongName> 103 - Disclosure - Accumulated Other Comprehensive Loss (Details) - Schedule of accumulated balances for each classification of other comprehensive loss </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/ScheduleofaccumulatedbalancesforeachclassificationofothercomprehensivelossTable </Role>
<ShortName> Accumulated Other Comprehensive Loss (Details) - Schedule of accumulated balances for each classification of other comprehensive loss </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/AccumulatedOtherComprehensiveLossTables </ParentRole>
<Position> 104 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R105.htm </HtmlFileName>
<LongName> 104 - Disclosure - Commitments and Contingencies (Details) </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/CommitmentsandContingenciesDetails </Role>
<ShortName> Commitments and Contingencies (Details) </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/CommitmentsandContingencies </ParentRole>
<Position> 105 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R106.htm </HtmlFileName>
<LongName> 105 - Disclosure - Related Party Transactions (Details) </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/RelatedPartyTransactionsDetails </Role>
<ShortName> Related Party Transactions (Details) </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/RelatedPartyTransactions </ParentRole>
<Position> 106 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R107.htm </HtmlFileName>
<LongName> 106 - Disclosure - Defined Contribution Plans (Details) </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/DefinedContributionPlansDetails </Role>
<ShortName> Defined Contribution Plans (Details) </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/DefinedContributionPlans </ParentRole>
<Position> 107 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R108.htm </HtmlFileName>
<LongName> 107 - Disclosure - Business Segment Information (Details) </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/BusinessSegmentInformationDetails </Role>
<ShortName> Business Segment Information (Details) </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/BusinessSegmentInformationTables </ParentRole>
<Position> 108 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R109.htm </HtmlFileName>
<LongName> 108 - Disclosure - Business Segment Information (Details) - Schedule of operating results of business segments </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/ScheduleofoperatingresultsofbusinesssegmentsTable </Role>
<ShortName> Business Segment Information (Details) - Schedule of operating results of business segments </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/BusinessSegmentInformationTables </ParentRole>
<Position> 109 </Position>
</Report>
<Report instance="f10k2020_idtcorporation.htm">
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<HtmlFileName> R110.htm </HtmlFileName>
<LongName> 109 - Disclosure - Business Segment Information (Details) - Schedule of net long-lived assets and total assets by geographic areas </LongName>
<ReportType> Sheet </ReportType>
<Role> http://www.www.idt.net/role/ScheduleofnetlonglivedassetsandtotalassetsbygeographicareasTable </Role>
<ShortName> Business Segment Information (Details) - Schedule of net long-lived assets and total assets by geographic areas </ShortName>
<MenuCategory> Details </MenuCategory>
<ParentRole> http://www.www.idt.net/role/BusinessSegmentInformationTables </ParentRole>
<Position> 110 </Position>
</Report>
<Report>
<IsDefault> false </IsDefault>
<HasEmbeddedReports> false </HasEmbeddedReports>
<LongName> All Reports </LongName>
<ReportType> Book </ReportType>
<ShortName> All Reports </ShortName>
</Report>
</MyReports>
<InputFiles>
<File doctype="10-K" original="f10k2020_idtcorporation.htm"> f10k2020_idtcorporation.htm </File>
<File> f10k2020ex21-01_idtcorp.htm </File>
<File> f10k2020ex23-01_idtcorp.htm </File>
<File> f10k2020ex23-02_idtcorp.htm </File>
<File> f10k2020ex31-01_idtcorp.htm </File>
<File> f10k2020ex31-02_idtcorp.htm </File>
<File> f10k2020ex32-01_idtcorp.htm </File>
<File> f10k2020ex32-02_idtcorp.htm </File>
<File> idt-20200731.xsd </File>
<File> idt-20200731_cal.xml </File>
<File> idt-20200731_def.xml </File>
<File> idt-20200731_lab.xml </File>
<File> idt-20200731_pre.xml </File>
</InputFiles>
<SupplementalFiles/>
<BaseTaxonomies>
<BaseTaxonomy> http://fasb.org/srt/2020-01-31 </BaseTaxonomy>
<BaseTaxonomy> http://xbrl.sec.gov/country/2020-01-31 </BaseTaxonomy>
<BaseTaxonomy> http://fasb.org/us-gaap/2020-01-31 </BaseTaxonomy>
<BaseTaxonomy> http://xbrl.sec.gov/dei/2019-01-31 </BaseTaxonomy>
</BaseTaxonomies>
<HasPresentationLinkbase> true </HasPresentationLinkbase>
<HasCalculationLinkbase> true </HasCalculationLinkbase>
</FilingSummary>


1 Subsequent Filing that References this Filing

  As Of               Filer                 Filing    For·On·As Docs:Size             Issuer                      Filing Agent

12/22/20  Idt Corp.                         10-K/A      7/31/20   12:298K                                   EdgarAgents LLC/FA


8 Previous Filings that this Filing References

  As Of               Filer                 Filing    For·On·As Docs:Size             Issuer                      Filing Agent

 4/07/20  Idt Corp.                         8-K:5,9     4/06/20    2:123K                                   EdgarAgents LLC/FA
12/05/17  Idt Corp.                         8-K:2,5,9  12/05/17    3:339K                                   EdgarAgents LLC/FA
10/16/17  Idt Corp.                         10-K        7/31/17  131:9.7M                                   EdgarAgents LLC/FA
12/20/16  Idt Corp.                         8-K:5,9    12/14/16    2:105K                                   EdgarAgents LLC/FA
10/14/16  Idt Corp.                         S-8        10/14/16    4:233K                                   EdgarAgents LLC/FA
 1/14/15  Idt Corp.                         8-K:5,9     1/12/15    2:94K                                    EdgarAgents LLC/FA
11/05/13  Idt Corp.                         DEF 14A    12/16/13    1:569K                                   Donnelley … Solutions/FA
 4/05/11  Idt Corp.                         8-K:3,5,8,9 4/04/11    3:136K                                   EdgarAgents LLC/FA
Top
Filing Submission 0001213900-20-031279   –   Alternative Formats (Word / Rich Text, HTML, Plain Text, et al.)

Copyright © 2024 Fran Finnegan & Company LLC – All Rights Reserved.
AboutPrivacyRedactionsHelp — Wed., May 1, 12:22:31.2pm ET