Accrued interest receivable

No definition available.

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

- Definition

allowance for credit losses.

+ References

No definition available.

+ Details

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

- Definition

Governmental issuer loans commitment.

+ References

No definition available.

+ Details

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

- Definition

Governmental issuer loans.

+ References

No definition available.

+ Details

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

- Definition

loan maturity date.

+ References

No definition available.

+ Details

Name:	ghi_LoanMaturityDate
Namespace Prefix:	ghi_
Data Type:	xbrli:dateItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of variable interest entities owned.

+ References

No definition available.

+ Details

Name:	ghi_NumberOfVariableInterestEntities
Namespace Prefix:	ghi_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Partnership recognized loan fee.

+ References

No definition available.

+ Details

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

- Definition

Percentage of collection from notes receivable including accrued interest.

+ References

No definition available.

+ Details

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

- Definition

This is the principal amount outstanding for securitized loans only (across all types of loans).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=121570589&loc=d3e107314-111719

+ Details

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

- Definition

The cash inflow associated with principal collections from a borrowing supported by a written promise to pay an obligation.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126954810&loc=d3e3179-108585

+ Details

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

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=ghi_GovernmentalIssuerLoansMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=ghi_PropertyLoansMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis=ghi_MagnoliaHeightsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis=ghi_OasisAtTwinLakesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_RealEstateAndAccumulatedDepreciationDescriptionOfPropertyAxis=ghi_ScharbauerFlatsApartmentsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Governmental Issuer Loans - Additional Information (Details)	1 Months Ended
	Jun. 30, 2023 USD ($) Entities Property	Jan. 01, 2023 USD ($)	Dec. 31, 2022 USD ($) Property	Jun. 30, 2022 USD ($)
Governmental Issuer Loans [Line Items]
Number of Variable Interest Entities \| Property	31		35
Allowance for credit losses		$ 5,900,000
Governmental Issuer Loans [Member]
Governmental Issuer Loans [Line Items]
Accrued interest receivable	$ 2,700,000		$ 3,800,000
Number of Variable Interest Entities \| Entities	2
Outstanding principal	$ 215,700,000
Allowance for credit losses	1,800,000
Property Loans [Member]
Governmental Issuer Loans [Line Items]
Outstanding principal	95,400,000
Magnolia Heights [Member] \| Governmental Issuer Loans [Member]
Governmental Issuer Loans [Line Items]
Total Commitment				$ 20,400,000
Oasis at Twin Lakes [Member] \| Governmental Issuer Loans [Member]
Governmental Issuer Loans [Line Items]
Amount received as payment in full for outstanding principal and accrued interest upon redemption	$ 34,100,000
Percentage of collection from notes receivable including accrued interest	100.00%
Scharbauer Flats Apartments [Member]
Governmental Issuer Loans [Line Items]
Partnership recognized loan fee	$ 33,000
Loan maturity date	Jan. 01, 2024
Scharbauer Flats Apartments [Member] \| Governmental Issuer Loans [Member]
Governmental Issuer Loans [Line Items]
Partnership recognized loan fee	$ 100,000
Loan maturity date	Jan. 01, 2024