Investment in tenancy-in-common (Schedule of balance sheet of Pierre Property) (Details) - USD ($) $ in Thousands	Apr. 30, 2021	Jan. 31, 2021	Oct. 31, 2020	Apr. 30, 2020	Jan. 31, 2020	Oct. 31, 2019
Schedule of Equity Method Investments [Line Items]
Real estate, net	$ 274,241		$ 278,150
Cash and cash equivalents	38,627		36,860	$ 31,751
Tenants' security accounts	1,395		1,408
Receivables and other assets	1,167		1,811
Total Assets	351,767		355,215
Mortgages payable, net of unamortized debt issuance costs	302,384		305,430
Accounts payable and accrued expenses	2,837		2,277
Tenants' security deposits	2,068		2,124
Deferred revenue	908		1,043
Equity	32,299	$ 31,920	30,863	$ 41,205	$ 13,277	$ 16,048
Total Liabilities and Equity	351,767		355,215
FREIT's investment in TIC (65% interest)	19,533		20,101
Pierre Property [Member]
Schedule of Equity Method Investments [Line Items]
Real estate, net	79,052		80,041
Cash and cash equivalents	580		754
Tenants' security accounts	510		523
Receivables and other assets	601		468
Total Assets	80,743		81,786
Mortgages payable, net of unamortized debt issuance costs	49,823		49,956
Accounts payable and accrued expenses	280		314
Tenants' security deposits	507		535
Deferred revenue	82		56
Equity	30,051		30,925
Total Liabilities and Equity	80,743		81,786
FREIT's investment in TIC (65% interest)	$ 19,533		$ 20,101