Subsequent Events - Summary Of Key Terms Of Property Loans Redeemed (Details)	1 Months Ended
Feb. 22, 2024 USD ($) Unit	Jan. 31, 2022 USD ($)
Subsequent Event [Line Items]
Principal Outstanding at Date of Redemption		$ 61,055,000
T O B Trust [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Principal Outstanding at Date of Redemption	$ 71,823,194
T O B Trust [Member] \| Osprey Village [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Month Redeemed	February 2024
Units \| Unit	383
Stated Maturity Date	Aug. 01, 2024
Principal Outstanding at Date of Redemption	$ 14,998,296
T O B Trust [Member] \| Osprey Village [Member] \| SOFR [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Interest Rate	3.07%
T O B Trust [Member] \| Osprey Village Supplemental [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Month Redeemed	February 2024
Units \| Unit	383
Stated Maturity Date	Aug. 01, 2024
Principal Outstanding at Date of Redemption	$ 4,600,000
T O B Trust [Member] \| Osprey Village Supplemental [Member] \| SOFR [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Interest Rate	3.22%
T O B Trust [Member] \| Willow Place Apartments [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Month Redeemed	February 2024
Units \| Unit	182
Stated Maturity Date	Oct. 01, 2024
Principal Outstanding at Date of Redemption	$ 18,875,606
T O B Trust [Member] \| Willow Place Apartments [Member] \| SOFR [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Interest Rate	3.30%
T O B Trust [Member] \| Willow Place Apartments Supplemental [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Month Redeemed	February 2024
Units \| Unit	182
Stated Maturity Date	Oct. 01, 2024
Principal Outstanding at Date of Redemption	$ 1,115,320
T O B Trust [Member] \| Willow Place Apartments Supplemental [Member] \| SOFR [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Interest Rate	3.45%
T O B Trust [Member] \| Legacy Commons at Signal Hills [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Month Redeemed	February 2024
Units \| Unit	247
Stated Maturity Date	Feb. 01, 2024
Principal Outstanding at Date of Redemption	$ 32,233,972
T O B Trust [Member] \| Legacy Commons at Signal Hills [Member] \| SOFR [Member] \| Subsequent Event [Member]
Subsequent Event [Line Items]
Interest Rate	3.07%

Investment owned, redemption month.

No definition available.

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Namespace Prefix:	ghi_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Mortgage loans on real estate, redemption, face amount.

+ References

No definition available.

+ Details

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Namespace Prefix:	ghi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Maturity date 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, in YYYY-MM-DD format.

+ References

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

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 948
-SubTopic 310
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-29(Column C))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479851/948-310-S99-1

+ Details

Name:	srt_MortgageLoanOnRealEstateFinalMaturityDate
Namespace Prefix:	srt_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- 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
-Name Regulation S-X (SX)
-Number 210
-Section 12
-Subsection 29
-Paragraph Column B
-Publisher SEC

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 948
-SubTopic 310
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.12-29(Column B))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479851/948-310-S99-1

+ Details

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Namespace Prefix:	srt_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of units in a real estate property owned as of the balance sheet date.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 830
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481674/830-30-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 855
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483399/855-10-50-2

+ Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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- Details

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