Percentage of contractual right to receive additional shares.

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- Definition

Percentage of direct and indirect interest.

+ References

No definition available.

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- Definition

Cash received on stock transactions.

+ References

No definition available.

+ Details

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- Definition

Purchase shares of capital stock.

+ References

No definition available.

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- References

No definition available.

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- Definition

Remaining amount of investment.

+ References

No definition available.

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- Definition

Excess of issue price over par or stated value of the entity's capital stock and amounts received from other transactions involving the entity's stock or stockholders. Includes adjustments to additional paid in capital. Some examples of such adjustments include recording the issuance of debt with a beneficial conversion feature and certain tax consequences of equity instruments awarded to employees. Use this element for the aggregate amount of additional paid-in capital associated with common and preferred stock. For additional paid-in capital associated with only common stock, use the element additional paid in capital, common stock. For additional paid-in capital associated with only preferred stock, use the element additional paid in capital, preferred stock.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(30)(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28551-108399

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

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Balance Type:	credit
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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571

+ Details

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- Definition

Net Increase or Decrease in balance of noncontrolling interest in the subsidiary during the reporting period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 45
-Paragraph 16
-URI http://asc.fasb.org/extlink&oid=108774443&loc=SL4568740-111683

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- Definition

The cash inflow resulting from the sale of an interest in a corporate unit during the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3255-108585

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Balance Type:	debit
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- Definition

Amount of noncash expense for share-based payment arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Number of options outstanding, including both vested and non-vested 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
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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 (c)(1)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

+ Details

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Percentage of subsidiary's or equity method investee's stock owned by parent immediately after all stock transactions.

+ References

No definition available.

+ Details

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Rafael Holdings, Inc. Spin-Off (Details Textual) - USD ($) $ in Thousands		1 Months Ended		12 Months Ended
	Mar. 02, 2017	Nov. 30, 2017	Sep. 30, 2016	Jul. 31, 2019	Jul. 31, 2018	Jul. 31, 2017	Mar. 31, 2018	Sep. 19, 2017	Sep. 14, 2017
Rafael Holdings, Inc. Spin-Off (Textual)
Options to purchase aggregate common stock				1,223,000	1,243,000
Stock-based compensation expense				$ 2,236	$ 3,581	$ 3,740
Purchase price						10,000
Purchase shares of capital stock percentage				56.00%
Additional paid-in capital				$ 273,313	294,047
Noncontrolling Interest [Member]
Rafael Holdings, Inc. Spin-Off (Textual)
Purchase price						7,250
Howard S. Jonas [Member]
Rafael Holdings, Inc. Spin-Off (Textual)
Percentage of direct and indirect interest	10.00%
Purchase price	$ 1,000
Howard S. Jonas [Member] \| Noncontrolling Interest [Member]
Rafael Holdings, Inc. Spin-Off (Textual)
Purchase of stock of subsidiary	1,200
Howard S. Jonas [Member] \| Additional Paid-in Capital [Member]
Rafael Holdings, Inc. Spin-Off (Textual)
Purchase of stock of subsidiary	$ 200
Rafael Class B Common Stock [Member]
Rafael Holdings, Inc. Spin-Off (Textual)
Options to purchase aggregate common stock							600
Rafael Holdings Inc [Member]
Rafael Holdings, Inc. Spin-Off (Textual)
Stock-based compensation expense					$ 200
Idt Corporation Option Holder [Member]
Rafael Holdings, Inc. Spin-Off (Textual)
Options to purchase aggregate common stock							1,300
Lipomedix Pharmaceuticals Ltd [Member]
Rafael Holdings, Inc. Spin-Off (Textual)
Percentage of non-operating subsidiary		50.60%
IDT-Rafael Holdings, LLC [Member]
Rafael Holdings, Inc. Spin-Off (Textual)
Percentage of contractual right to receive additional shares				10.00%
Percentage of non-operating subsidiary				90.00%
IDT-Rafael Holdings, LLC [Member] \| Howard S. Jonas [Member]
Rafael Holdings, Inc. Spin-Off (Textual)
Percentage of contractual right to receive additional shares								9.00%	1.00%
IDT-Rafael Holdings, LLC [Member] \| Idt Corporation [Member]
Rafael Holdings, Inc. Spin-Off (Textual)
Percentage of contractual right to receive additional shares									9.00%
CS Pharma Holdings, LLC [Member]
Rafael Holdings, Inc. Spin-Off (Textual)
Purchase price						10,000
Noncontrolling interests						7,200
Additional paid-in capital						$ 2,800
Convertible promissory note, principal amount			$ 2,000
Owned percentage			50.00%
CS Pharma Holdings, LLC [Member] \| Convertible Promissory Notes [Member]
Rafael Holdings, Inc. Spin-Off (Textual)
Additional amount of investment funded			$ 8,000
Convertible promissory note, principal amount			$ 10,000