Investment in tenancy-in-common (Schedule of balance sheet of Pierre Property) (Details) - USD ($) $ in Thousands	Jul. 31, 2022	Apr. 30, 2022	Jan. 31, 2022	Oct. 31, 2021	Jul. 31, 2021	Apr. 30, 2021	Jan. 31, 2021	Oct. 31, 2020
Schedule of Equity Method Investments [Line Items]
Real estate, net	$ 95,986			$ 270,634
Cash and cash equivalents	98,307			35,891	$ 36,359
Tenants' security accounts	1,038			1,340
Receivables and other assets	571			1,622
Total assets	226,803			346,105
Mortgages payable, net of unamortized debt issuance costs	138,300			299,876
Accounts payable and accrued expenses	1,534			2,375
Tenants' security deposits	1,294			2,039
Deferred revenue	373			1,143
Equity	82,969	$ 82,727	$ 82,029	31,951	$ 31,716	$ 32,299	$ 31,920	$ 30,863
Total liabilities & equity	226,803			346,105
FREIT's investment in TIC (65% interest)	18,927			19,383
Pierre Property [Member]
Schedule of Equity Method Investments [Line Items]
Real estate, net	76,525			78,023
Cash and cash equivalents	1,801			1,338
Tenants' security accounts	456			484
Receivables and other assets	640			510
Total assets	79,422			80,355
Mortgages payable, net of unamortized debt issuance costs	49,492			49,691
Accounts payable and accrued expenses	221			261
Tenants' security deposits	461			484
Deferred revenue	129			99
Equity	29,119			29,820
Total liabilities & equity	$ 79,422			$ 80,355