Interest rate swap contracts (Details) - USD ($)	1 Months Ended	12 Months Ended
	Sep. 29, 2016	Oct. 31, 2017	Oct. 31, 2016	Oct. 31, 2015	Apr. 22, 2016	Dec. 26, 2012
Mortgages and construction loan payable		$ 323,435,000	$ 329,719,000
Interest rate swap contract assets		1,600,000	91,000
Unrealized gain (loss) on derivatives		2,952,000	725,000	$ 1,581,000
Interest rate swap contract liabilities		439,000	1,882,000
Wayne PSC, LLC Loan [Member]
Refinanced loan amount	$ 24,200,000
Loan amount		25,100,000
Notional amount of interest rate swap		$ 25,200,000
Fixed interest rate		3.625%
Basis points, interest rate	2.20%
Maturity date of loan	Oct. 01, 2026	Oct. 01, 2026
People's United Bank [Member]
Loan amount	$ 25,800,000
Mortgages and construction loan payable		$ 20,400,000			$ 2,320,000
Notional amount of interest rate swap		$ 20,400,000
People's United Bank [Member] | Tranche Two [Member]
Loan amount					$ 2,320,000
Fixed interest rate		3.53%
Basis points, interest rate		2.10%
Maturity date of loan		Jan. 03, 2023
People's United Bank [Member] | Tranche One [Member]
Loan amount						$ 20,000,000
Fixed interest rate		3.81%
Basis points, interest rate		2.10%
Maturity date of loan		Jan. 03, 2023
Provident Bank [Member]
Loan amount		$ 16,200,000
Mortgages and construction loan payable
Notional amount of interest rate swap		$ 16,200,000
Maturity date		Dec. 15, 2024
Fixed interest rate		3.75%
Basis points, interest rate		1.25%
Maturity date of loan		Oct. 27, 2020
Regency Swap [Member]
Interest rate swap contract liabilities		$ 439,000	1,361,000	945,000
Damascus Centre Swap [Member]
Interest rate swap contract liabilities		275,000	521,000	$ 121,000
Wayne PSC swap [Member]
Interest rate swap contract assets		$ 1,325,000	$ 91,000