Selected quarterly financial data (Details) - USD ($) $ / shares in Units, $ in Thousands		1 Months Ended		3 Months Ended												12 Months Ended
	Feb. 08, 2019	Jun. 30, 2020	Feb. 28, 2020	Oct. 31, 2020		Jul. 31, 2020		Apr. 30, 2020		Jan. 31, 2020	Oct. 31, 2019	Jul. 31, 2019	Apr. 30, 2019		Jan. 31, 2019	Oct. 31, 2020	Oct. 31, 2019	Oct. 31, 2018
Revenue				$ 11,297		$ 12,149	[1]	$ 13,688		$ 15,593	$ 15,308	$ 15,255	$ 14,786		$ 14,928	$ 52,727	$ 60,277	$ 57,997
Expenses				18,772	[2]	12,469	[1]	(13,448)	[3]	17,614	15,045	14,990	13,956	[4]	14,493	35,407	58,484
Net income				(7,475)		(320)		27,136		(2,021)	263	265	830		435	17,320	1,793	966
Net loss (income) attributable to noncontrolling interests in subsidiaries				3,251		139		84		(241)	80	(66)	(44)		24	3,233	(6)	517
Net (loss) income attributable to common equity				$ (4,224)		$ (181)		$ 27,220		$ (2,262)	$ 343	$ 199	$ 786		$ 459	$ 20,553	$ 1,787	$ 1,483
(Loss) Earnings per share - basic and diluted				$ (0.60)	[2]	$ (0.02)	[1]	$ 3.88	[3]	$ (0.32)	$ 0.05	$ 0.03	$ 0.11	[4]	$ 0.07	$ 2.94	$ 0.26	$ 0.21
Dividends declared per share											$ 0.20	$ 0.125	$ 0.125		$ 0.15		$ 0.60	$ 0.15
Deferred rents - straight lining																$ 397	$ (410)	$ (605)
Gain on sale of property per share	$ 0.12		$ 3.96													$ 0.62
Gain from sales	$ 800		$ 27,700
Straight-line rent receivable				$ 400												$ 400
Increase in expense for reserve of uncollectible rents																300
Increase in expense for reserve of uncollectible rents with consolidated impact																200
Unamortized leasing commissions fully expensed in a net impact of net income																900
Tenant improvements related to Cobb Theatre with net book value																7,300
FREIT [Member]
Unamortized leasing commissions fully expensed in a net impact of net income																500
Tenant improvements related to Cobb Theatre with net book value																$ 4,400
Cobb theater Rotunda retail property [Mmeber]
Gain on sale of property per share		$ 0.07

[1] Includes impact of the rejection of the lease for Cobb Theatre at the Rotunda retail property as of June 30, 2020 resulting in the reversal against revenue of uncollected rents in the amount of approximately $0.3 million and a straight-line rent receivable of approximately $0.4 million and the write-off of unamortized leasing commissions in the amount of approximately $0.2 million resulting in a net impact of approximately $0.9 million (with a consolidated impact to FREIT of approximately $0.5 million). ($0.07 per share)

[2] Includes write-off of Cobb Theatre's tenant improvements of approximately $7.3 million (with a consolidated impact to FREIT of approximately $4.4 million) at the Rotunda retail property due to COVID-19. ($0.62 per share)

[3] Includes $27.7 million gain on deconsolidation of subsidiary related to the Pierre Towers property which was deconsolidated from FREIT's operating results due to the conversion to a tenancy-in-common form of ownership on February 28, 2020. ($3.96 per share)

[4] Includes $0.8 million gain on sale of the Patchogue, New York property sold on February 8, 2019. ($0.12 per share)