BASIS OF PRESENTATION AND SIGNIFICANT ACCOUNTING POLICIES (Details Narrative) - USD ($)	6 Months Ended
Dec. 31, 2021	Jun. 30, 2021
Cash received in liquidation	$ 5,013,000
Other investment net [Member]
Other assets, current		$ 41,000
Finance lease [Member]
Accounts payable		$ 664,000
Interstate management company LLC [Member]
Management fee payable, percentage on revenue	1.70%
Portsmouth Inc [Member]
Equity investment interest	75.00%
Santa Fe [Member]
Equity investment interest	83.70%
Cash received in liquidation	$ 221,000
Shares received in liquidation	18,641
Santa Fe [Member] \| Chairman and CEO [Member]
Equity investment interest	3.70%
Cash received in liquidation	$ 221,000
Shares received in liquidation	18,641
Santa Fe [Member] \| Portsmouth Inc [Member]
Noncontrolling Interest, Ownership Percentage by Parent	68.80%
Portsmouth [Member]
Cash received in liquidation	$ 5,013,000
Shares received in liquidation	422,998
Portsmouth [Member] \| President, Chairman of the Board and Chief Executive Officer, John Winfield [Member]
Equity investment interest	2.50%
Justice Investors Limited Partnership And Intergroup [Member]
Equity investment interest	100.00%

Cash received in liquidation.

No definition available.

Name:	INTG_CashReceivedInLiquidation
Namespace Prefix:	INTG_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Management fee payable percentage on revenue.

+ References

No definition available.

+ Details

Name:	INTG_ManagementFeePayablePercentageOnRevenue
Namespace Prefix:	INTG_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Shares received in liquidation.

+ References

No definition available.

+ Details

Name:	INTG_SharesReceivedInLiquidation
Namespace Prefix:	INTG_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of liabilities incurred and payable to vendors for goods and services received, and accrued liabilities classified as other.

+ References

No definition available.

+ Details

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

- 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

Name:	us-gaap_EquityMethodInvestmentOwnershipPercentage
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The parent entity's interest in net assets of the subsidiary, expressed as a percentage.

+ References

No definition available.

+ Details

Name:	us-gaap_MinorityInterestOwnershipPercentageByParent
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of current assets classified as other.

+ 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 210.5-02.8)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 852
-SubTopic 10
-Section 55
-Paragraph 10
-URI http://asc.fasb.org/extlink&oid=84165509&loc=d3e56426-112766

+ Details

Name:	us-gaap_OtherAssetsCurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

Name:	us-gaap_ReclassificationTypeAxis=INTG_OtherInvestmentNetMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ReclassificationTypeAxis=INTG_FinanceLeaseMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RelatedPartyTransactionsByRelatedPartyAxis=INTG_InterstateManagementCompanyLLCMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_OwnershipAxis=INTG_PortsmouthSquareIncMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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

- Details

Name:	srt_TitleOfIndividualAxis=INTG_ChairmanAndCEOMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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

- Details

Name:	srt_TitleOfIndividualAxis=INTG_PresidentChairmanBoardChiefExecutiveOfficerJohnWinfieldMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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