Basis of Presentation - Additional Information (Details)	6 Months Ended
Jun. 30, 2026 Preferredunit Rating
Segment Reporting Information [Line Items]
Number of partnership preferred units \| Preferredunit	3
Location, Statement of Financial Position, Balance [Axis]: ghi:TaxExemptAndOtherInvestments
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

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.

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+ Details