Loan fee percentage.

No definition available.

Name:	INTG_LoanFeePercentage
Namespace Prefix:	INTG_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of shares exchanged.

+ References

No definition available.

+ Details

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Namespace Prefix:	INTG_
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Balance Type:	na
Period Type:	duration

- Definition

Face amount or stated value per share of common stock.

+ References

+ Details

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Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Description of voting rights of common stock. Includes eligibility to vote and votes per share owned. Include also, if any, unusual voting rights.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
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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
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-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Carrying amount of the unpaid portion of the fee payable to the managing member or general partner for management of the fund or trust.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Number of new stock issued during the period.

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-SubTopic 10
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Balance Type:	na
Period Type:	duration

- Definition

Including the current and noncurrent portions, carrying value as of the balance sheet date of uncollateralized debt obligations (with maturities initially due after one year or beyond the operating cycle if longer).

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Balance Type:	credit
Period Type:	instant

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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- Details

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Related Party Transactions (Details Narrative) - USD ($)	Feb. 05, 2020	Sep. 28, 2018	Jul. 02, 2014	Jun. 30, 2020	Jun. 30, 2019
Debt instrument term		5 years
Common stock, par value				$ 0.01	$ 0.01
Justice Operating Company, LLC [Member]
Fee payable				$ 1,550,000	$ 200,000
Santa Fe [Member] \| Contribution Agreement [Member]
Number of common stock shares received	97,500
Common stock, par value	$ 0.10
Number of shares exchanged	4,460
Common stock voting rights	Company had the power to vote 86.3% of the voting shares of Santa Fe, which includes the power to vote an approximately 4% interest in the common stock in Santa Fe owned by the Company's Chairman and CEO, John V. Winfield, pursuant to a voting trust agreement entered into on June 30, 1998. Subsequent to this issuance, the Company has the power to vote 87.4% of the issued and outstanding common stock of Santa Fe, which includes the power to vote an approximately 3.7% interest in the common stock in Santa Fe under the aforementioned voting trust agreement. Mr. Winfield, Chairman of the Board of both the Company and Santa Fe, is a control person of both entities.
InterGroup [Member]
Debt principal amount			$ 4,250,000
Debt interest rate			12.00%
Debt instrument term			2 years
Loan fee percentage			3.00%
Unsecured loan				$ 3,000,000	$ 3,000,000