XML 77 R63.htm IDEA: XBRL DOCUMENT
v3.24.0.1

Basis of Presentation - Additional Information (Details) | 12 Months Ended
--- | ---
Dec. 31, 2023 Rating Preferredunit
Segment Reporting Information [Line Items] |
Number of partnership preferred units | Preferredunit | 3
Tax-exempt and Other Investments [Member] |
Segment Reporting Information [Line Items] |
Assets percentage | 25.00%
Maximum [Member] |
Segment Reporting Information [Line Items] |
Required rating for tax exempted investments other than mortgage revenue bonds | 4
Minimum [Member] |
Segment Reporting Information [Line Items] |
Required rating for tax exempted investments other than mortgage revenue bonds | 1

X
- Definition Assets percentage. + References No definition available. + Details
Name: | ghi_AssetsPercentage
Namespace Prefix: | ghi_
Data Type: | dtr-types:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Number of partnership preferred units. + References No definition available. + Details
Name: | ghi_NumberOfPartnershipPreferredUnits
Namespace Prefix: | ghi_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Required rating for tax exempted investments other than mortgage revenue bonds. + References No definition available. + Details
Name: | ghi_RequiredRatingForTaxExemptedInvestmentsOtherThanMortgageRevenueBonds
Namespace Prefix: | ghi_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_SegmentReportingInformationLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_BalanceSheetLocationAxis=ghi_TaxExemptSecuritiesOtherThanMRBsAndOtherInvestmentsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_RangeAxis=srt_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |