XML 114 R100.htm IDEA: XBRL DOCUMENT
v3.20.2

Stock-Based Compensation (Details) - USD ($) |  |  |  | 1 Months Ended | 12 Months Ended
--- | --- | --- | --- | --- | ---
Jan. 06, 2020 | Jan. 06, 2020 | Dec. 12, 2019 | Dec. 13, 2018 | Sep. 30, 2020 | Jul. 31, 2020 | Jul. 31, 2019
Stock-Based Compensation (Details) [Line Items] |  |  |  |  |  |  |
Option term, description |  |  |  |  |  | Share awards generally vest on a graded basis over three years of service. |
Common stock shares issued for vested (in Shares) |  |  |  |  |  | 100,000 |
Subsequent Event [Member] |  |  |  |  |  |  |
Stock-Based Compensation (Details) [Line Items] |  |  |  |  |  |  |
Business unit |  |  |  |  | $ 100,000,000 |  |
Stock Options [Member] |  |  |  |  |  |  |
Stock-Based Compensation (Details) [Line Items] |  |  |  |  |  |  |
Total intrinsic value of options exercised during the period |  |  |  |  |  | $ 16,000 |
Restricted Stock [Member] |  |  |  |  |  |  |
Stock-Based Compensation (Details) [Line Items] |  |  |  |  |  |  |
Total unrecognized non-vested stock-based compensation |  |  |  |  |  | $ 500,000 |
Non-vested stock options, weighted-average period |  |  |  |  |  | 9 months 18 days |
Total grant date fair value |  |  |  |  |  | $ 300,000 | $ 700,000
Deferred Stock Units [Member] |  |  |  |  |  |  |
Stock-Based Compensation (Details) [Line Items] |  |  |  |  |  |  |
Total unrecognized non-vested stock-based compensation |  |  |  |  |  | $ 1,300,000 |
Non-vested stock options, weighted-average period |  |  |  |  |  | 8 months 12 days |
Total grant date fair value |  |  |  |  |  | $ 1,100,000 |
Deferred Stock Units [Member] |  |  |  |  |  |  |
Stock-Based Compensation (Details) [Line Items] |  |  |  |  |  |  |
Delayed vesting shares (in Shares) |  | 38,024 |  |  |  |  |
Common Class B [Member] |  |  |  |  |  |  |
Stock-Based Compensation (Details) [Line Items] |  |  |  |  |  |  |
Additional shares available stock option incentive plan for grants (in Shares) |  |  | 400,000 | 100,000 |  |  |
Shares of common stock reserved for award under 2015 stock option and incentive plan (in Shares) |  |  |  |  |  | 1,600,000 |
Shares of common stock available for future grants (in Shares) |  |  |  |  |  | 600,000 |
Common stock shares issued for vested (in Shares) |  |  |  |  |  | 32,000 |
Common Class B [Member] | Deferred Stock Units [Member] |  |  |  |  |  |  |
Stock-Based Compensation (Details) [Line Items] |  |  |  |  |  |  |
Vesting date, description |  |  |  |  |  | the DSUs will vest in three equal amounts on each of January 6, 2020, January 5, 2021, and January 5, 2022. The number of shares that will be issuable on each vesting date will vary between 50% to 200% of the number of DSUs that vest on that vesting date, depending on the market price for the underlying Class B common stock on the vesting date relative to the market price at the time of the grant. |
Common Class B [Member] | Deferred Stock Units [Member] |  |  |  |  |  |  |
Stock-Based Compensation (Details) [Line Items] |  |  |  |  |  |  |
Common stock shares issued for vested (in Shares) | 100,284 |  |  |  |  |  |

X
- Definition This value for restricted equity vesting condition business unit fair value. + References No definition available. + Details
Name: | idt_RestrictedEquityVestingConditionBusinessUnitFairValue
Namespace Prefix: | idt_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Share-based compensation arrangement by share based payment award equity instruments other than options vesting deferred in period. + References No definition available. + Details
Name: | idt_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestingDeferredInPeriod
Namespace Prefix: | idt_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- References No definition available. + Details
Name: | idt_StockBasedCompensationDetailsLineItems
Namespace Prefix: | idt_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
Name: | us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedPeriodForRecognition1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (i) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
Name: | us-gaap_EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognizedShareBasedAwardsOtherThanOptions
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Description of service or performance condition required to be met for earning right to award under share-based payment arrangement. Includes, but is not limited to, combination of market, performance or service condition. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardAwardVestingRights
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Description of terms of share-based payment arrangement. Includes, but is not limited to, type of award or grantee and reason for issuance. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5047-113901 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardDescription
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2)(iii)(2) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriod
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (d)(2) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Number of additional shares authorized for issuance under share-based payment arrangement. + References No definition available. + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfAdditionalSharesAuthorized
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of shares authorized for issuance under share-based payment arrangement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (d)(2) -URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901 + Details
Name: | us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Details
Name: | us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_AwardTypeAxis=us-gaap_OptionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_AwardTypeAxis=us-gaap_RestrictedStockMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_AwardTypeAxis=idt_DeferredStockUnitsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementEquityComponentsAxis=idt_DeferredStockUnitsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementClassOfStockAxis=us-gaap_CommonClassBMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |