Represents the maturity date.

No definition available.

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- Definition

Mortgage Notes Payable Line Items.

+ References

No definition available.

+ Details

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- Definition

Amount of contractual principal due at origination of mortgage loan within investment in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 12
-Paragraph Column F
-Subsection 29

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 948
-SubTopic 310
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-29(Column F))
-URI http://asc.fasb.org/extlink&oid=120402547&loc=d3e617274-123014

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

Interest rate of mortgage loan within investment in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 12
-Paragraph Column B
-Subsection 29

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 948
-SubTopic 310
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-29(Column B))
-URI http://asc.fasb.org/extlink&oid=120402547&loc=d3e617274-123014

+ Details

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- Definition

Description of contractual payment terms of mortgage loan within investment in mortgage loan on real estate by entity with substantial portion of business acquiring and holding investment real estate or interest in real estate. Includes, but is not limited to, whether mortgage loan is payable at level or varying amount to maturity, balloon payment requirement at maturity, and prepayment penalty.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 12
-Paragraph Column D
-Subsection 29

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 948
-SubTopic 310
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-29(Column D))
-URI http://asc.fasb.org/extlink&oid=120402547&loc=d3e617274-123014

+ Details

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Balance Type:	na
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- Definition

Description of minimum financial levels (for example, tangible net worth and working capital) and achievement of certain financial ratios (for example, working capital ratio and debt service coverage ratio), and adherence to certain clauses which generally require or restrict certain actions (for example, entering into a debt arrangement with equal or greater seniority, and selling or discontinuing a certain business segment or material subsidiary) to be in compliance with the covenant clauses of the debt agreement. May also include a discussion of the adverse consequences that would result if the entity violates or fails to satisfy the covenants.

+ 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(22))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=75038535&loc=d3e64711-112823

+ Details

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

- Definition

Gross amount of debt extinguished.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

+ 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 (b)
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3255-108585

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(f))
-URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

Name:	us-gaap_CreditFacilityAxis=us-gaap_RevolvingCreditFacilityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_MortgageLoansOnRealEstateLoanTypeAxis=INTG_MezzanineLoanMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_MortgageLoansOnRealEstateLoanTypeAxis=INTG_MortgageLoansMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	dei_LegalEntityAxis=INTG_NineUnitApartmentComplexMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_StatementGeographicalAxis=country_CA
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_MortgageLoansOnRealEstateLoanTypeAxis=INTG_UnitApartmentComplexMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_MortgageLoansOnRealEstateLoanTypeAxis=INTG_NewMortgageLoansMember
Namespace Prefix:
Data Type:	na
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- Details

Name:	srt_MortgageLoansOnRealEstateLoanTypeAxis=INTG_OneHundredAndFiftyUnitApartmentComplexMember
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Mortgage Notes Payable (Details Narrative) - USD ($)						1 Months Ended	12 Months Ended
Mortgage Notes Payable (Details Narrative) - USD ($)	Apr. 30, 2020	Jul. 31, 2019	Sep. 28, 2018	Aug. 31, 2018	Aug. 31, 2018	Sep. 30, 2018	Jun. 30, 2020	Jun. 30, 2019	May 12, 2017
Mortgage Notes Payable [Line Items]
Mortgage and mezzanine amount			$ 1,000,000
Bears interest percentage			4.75%
Proceeds from Lines of Credit				$ 995,000				$ 2,985,000
Debt Instrument coverage ratio Description							The DSCR for Operating has been below 1.00 for the last two quarters during fiscal year 2020 while it is required to maintain a DSCR of at least 1.10 to 1.00 for two consecutive quarters. However, such lockbox has been created and utilized from the loan inception and will be in place up to loan maturity regardless of the DSCR.
Revolving Credit Facility [Member]
Mortgage Notes Payable [Line Items]
Proceeds from Lines of Credit					$ 1,005,000
Mezzanine Loan [Member]
Mortgage Notes Payable [Line Items]
Mortgage and mezzanine amount		$ 20,000,000					$ 20,000,000		$ 20,000,000
Bears interest percentage		7.25%					9.75%
Mortgage loans, description							The term of the loan is 10 years with interest only due in the first three years and principle and interest on the remaining seven years of the loan based on a thirty-year amortization schedule.
Maturity Date		January 1, 2024					January 1, 2024
Mortgage Loans [Member]
Mortgage Notes Payable [Line Items]
Mortgage and mezzanine amount	$ 8,453,000						$ 97,000,000		$ 97,000,000
Bears interest percentage							5.275%
Maturity Date							January 2024
Mortgage Loans [Member] \| NineUnit Apartment Complex [Member]
Mortgage Notes Payable [Line Items]
Mortgage and mezzanine amount							$ 1,274,000
Bears interest percentage							3.09%
Mortgage loans, description							July 2030
Proceeds from Lines of Credit							$ 1,144,000
Mortgage Loans [Member] \| NineUnit Apartment Complex [Member] \| California [Member]
Mortgage Notes Payable [Line Items]
Mortgage and mezzanine amount							$ 2,600,000
Unit Apartment Complex [Member]
Mortgage Notes Payable [Line Items]
Mortgage and mezzanine amount						$ 995,000
Bears interest percentage						4.75%
Maturity Date						October 2048
Proceeds from Lines of Credit						$ 1,000,000
New Mortgage Loans [Member]
Mortgage Notes Payable [Line Items]
Mortgage and mezzanine amount	$ 18,370,000
Bears interest percentage	3.17%
Maturity Date	May 2030
Proceeds from Lines of Credit	$ 6,814,000
Extinguishment of Debt	687,000
150 Unit apartment Unit Complex [Member]
Mortgage Notes Payable [Line Items]
Mortgage and mezzanine amount	$ 2,469,000