Deferred fee plan (Details) - USD ($)	12 Months Ended
	Oct. 31, 2021	Oct. 31, 2020	Oct. 31, 2019	Dec. 31, 2019
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Dividends payable	$ 686,000		$ 1,357,000
Robert S. Hekemian [Member]
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Trustee fee expense	0	21,000	$ 214,000
Deferred Fee Plan [Member]
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Trustee fee expense	488,000	526,000
Deferred trustee fees	446,000	526,000
Deferred accrued interest	$ 1,021,000	$ 1,091,000
Basis spread on any deferred fee (percentage)	150.00%
Shares issued	27,176	29,134
Dividends payable	$ 42,000	$ 0
Cumulative fees	$ 1,454,000	$ 1,542,000
Deferred Fee Plan [Member] | Robert S. Hekemian [Member]
Deferred Compensation Arrangement with Individual, Excluding Share-based Payments and Postretirement Benefits [Line Items]
Lump sum accrued plan benefits payable related party				$ 4,800,000