Capital provided for joint venture.

No definition available.

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Namespace Prefix:	ghi_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Commitments and other guarantees.

+ References

No definition available.

+ Details

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

- Definition

Construction loan guarantee percentage upon occurrence of fraud borrower willful misconduct and bankruptcy.

+ References

No definition available.

+ Details

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

- Definition

Excess proceeds payable by partnership to the prior owner.

+ References

No definition available.

+ Details

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

- Definition

Excess proceeds payable by partnership under agreement.

+ References

No definition available.

+ Details

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Namespace Prefix:	ghi_
Data Type:	xbrli:monetaryItemType
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Period Type:	duration

- Definition

Guaranty agreement required partnership to maintain net worth amount.

+ References

No definition available.

+ Details

Name:	ghi_GuarantyAgreementRequiredPartnershipToMaintainNetWorthAmount
Namespace Prefix:	ghi_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Maturity of construction loan.

+ References

No definition available.

+ Details

Name:	ghi_MaturityOfConstructionLoan
Namespace Prefix:	ghi_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Partnership contributed capital provided for joint venture.

+ References

No definition available.

+ Details

Name:	ghi_PartnershipContributedCapitalProvidedForJointVenture
Namespace Prefix:	ghi_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Partnership recorded liability.

+ References

No definition available.

+ Details

Name:	ghi_PartnershipRecordedLiability
Namespace Prefix:	ghi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Percentage of capital provided for joint venture.

+ References

No definition available.

+ Details

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

- Definition

The estimated maximum percentage of possible loss from the contingency.

+ References

No definition available.

+ Details

Name:	ghi_PercentageOfLossContingencyRangeOfPossibleLossMaximum
Namespace Prefix:	ghi_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Sale of real estate ownership interest percentage.

+ References

No definition available.

+ Details

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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Year Of Guarantee Agreement Term Ending .

+ References

No definition available.

+ Details

Name:	ghi_YearOfGuaranteeAgreementTermEnding
Namespace Prefix:	ghi_
Data Type:	xbrli:gYearItemType
Balance Type:	na
Period Type:	duration

- Definition

This element represents the carrying value of a short-term real estate loan to finance building costs. The funds are disbursed as needed or in accordance with a prearranged plan; generally, a portion of the funds is disbursed at inception and the remainder as construction progresses. The money is repaid on completion of the project, usually from the proceeds of a mortgage loan. The rate is normally higher than the prime rate, and there is usually an origination fee. The effective yield on these loans tends to be high, and the lender has a security interest in the real property. Note that there are separate concepts for the current and noncurrent portions of long-term construction loans.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S50
-Paragraph 8
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480657/210-10-S50-8

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(19)(a)(7))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

+ Details

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

- Definition

The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 460
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482425/460-10-50-4

+ Details

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

- Definition

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 460
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482425/460-10-50-4

+ Details

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

- Definition

A payment from an investee, in which the investment basis has previously been reduced to zero. This amount reduces net cash used in operating activities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Subparagraph (b)
-SubTopic 10
-Topic 230
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-28

+ Details

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

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Commitments and Contingencies - Additional Information (Details) - USD ($)	1 Months Ended	6 Months Ended
	Dec. 31, 2022	Jun. 30, 2026	Dec. 31, 2025
Commitments And Other Guarantees [Line Items]
Percentage of capital provided for joint venture		10.00%
Partnership contributed capital provided for joint venture		$ 773,000
Capital provided for joint venture		15,100,000
Reported value of credit guaranties		344,000	$ 550,000
Reimbursement agreement amount		$ 1,700,000
Greens of Pine Glen [Member]
Commitments And Other Guarantees [Line Items]
Percentage of loss contingency, range of possible loss, maximum		75.00%
Loan purchase agreement expiry year		2027
Loan purchase agreement maximum exposure		$ 1,278,767
The 50/50 MF Property [Member]
Commitments And Other Guarantees [Line Items]
Ownership interest sold	100.00%
Park at Sondrio [Member]
Commitments And Other Guarantees [Line Items]
Excess proceeds payable by partnership under agreement		2,400,000
Park at Vietti [Member]
Commitments And Other Guarantees [Line Items]
Excess proceeds payable by partnership under agreement		2,100,000
Windsor Shores Apartments [Member]
Commitments And Other Guarantees [Line Items]
Excess proceeds payable by partnership under agreement		904,000
Century Plaza Apartments [Member]
Commitments And Other Guarantees [Line Items]
Excess proceeds payable by partnership under agreement		1,700,000
Excess proceeds payable by partnership to the prior owner		10,700,000
Partnership recorded liability		$ 393,000
Freestone Cresta Bella Bridge Loan [Member]
Commitments And Other Guarantees [Line Items]
Construction loan guarantee percentage upon occurrence of fraud, borrower willful misconduct and bankruptcy		100.00%
Net worth to be maintained as per guaranty agreement		$ 42,000,000
Construction loan		42,000,000
Freestone Cresta Bella Bridge Loan [Member] \| Minimum [Member]
Commitments And Other Guarantees [Line Items]
Net worth to be maintained as per guaranty agreement		$ 4,200,000
Forward Loan Purchase Agreement [Member]
Commitments And Other Guarantees [Line Items]
Loan purchase agreement expiry year		2027
Loan purchase agreement maximum exposure		$ 20,300,000
Construction loan		$ 152,300,000
Forward Loan Purchase Agreement [Member] \| Maximum [Member]
Commitments And Other Guarantees [Line Items]
Maturity of construction loan		7 years
Forward Loan Purchase Agreement [Member] \| Minimum [Member]
Commitments And Other Guarantees [Line Items]
Maturity of construction loan		5 years