Represents this element additional consideration received from sale of buildings.

No definition available.

Name:	intg_AdditionalConsiderationReceivedFromSaleOfBuildings
Namespace Prefix:	intg_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The difference between the carrying value and the sale price of buildings that were intended to be sold or held for capital appreciation or rental income. This element refers to the gain (loss) included in earnings and not to the cash proceeds of the sale.

+ References

No definition available.

+ Details

Name:	intg_GainLossOnSaleOfBuildings
Namespace Prefix:	intg_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Represents the number of apartment sold during the period.

+ References

No definition available.

+ Details

Name:	intg_NumberOfApartmentSold
Namespace Prefix:	intg_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Other real estate revenue not otherwise specified in the taxonomy.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.1(e))

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

+ Details

Name:	us-gaap_OtherRealEstateRevenue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The cash inflow from sale of buildings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Investing Activities

-URI http://asc.fasb.org/extlink&oid=6516133

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 12

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3179-108585

+ Details

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

- Details

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

- Definition

Carrying amount as of the balance sheet date of investments in land and buildings held for sale, excluding real estate considered to be inventory of the entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.1(f))

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

+ Details

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

INVESTMENT IN REAL ESTATE AND MORTGAGE AND OTHER NOTES PAYABLE (Details Textual) (USD $)	3 Months Ended		1 Months Ended	3 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Feb. 28, 2014 Apartment Building [Member]	Sep. 30, 2014 Apartment Building [Member]
Property, Plant and Equipment [Line Items]
Real Estate Held-for-sale			$ 15,800,000
Number Of Apartment Sold			249
Proceeds from Sale of Buildings			458,000
Gain Loss On Sale Of Buildings			208,000
Additional Consideration Received From Sale Of Buildings			250,000
Other Real Estate Revenue	$ 458,000	$ 0		$ 458,000