Interest rate cap and swap contracts (Details) - USD ($)			1 Months Ended	12 Months Ended
	Feb. 07, 2018	Dec. 07, 2017	Sep. 29, 2016	Oct. 31, 2019	Oct. 31, 2018	Oct. 31, 2017
Derivative [Line Items]
Interest rate swap contract assets					$ 4,434,000
Unrealized gain (loss) on derivatives				(160,000)	72,000
Net unrealized gain (loss) on interest rate swap contracts				(6,400,000)	3,113,000	2,952,000
Interest rate swap contract liabilities				2,126,000
Damascus Centre Swap [Member]
Derivative [Line Items]
Interest rate swap contract assets					955,000	275,000
Interest rate swap contract liabilities				179,000
Wayne PSC swap [Member]
Derivative [Line Items]
Interest rate swap contract assets					2,452,000	1,325,000
Interest rate swap contract liabilities				53,000
Regency Swap [Member]
Derivative [Line Items]
Interest rate swap contract assets					408,000
Interest rate swap contract liabilities				860,000		$ 439,000
Monmouth swap [Member]
Derivative [Line Items]
Interest rate swap contract assets					460,000
Interest rate swap contract liabilities				1,034,000
Station Place on Monmouth, LLC [Member]
Derivative [Line Items]
Percentage of acquisition		100.00%
Loan amount		$ 12,350,000
Notional amount of interest rate swap		$ 12,350,000
Fixed interest rate		4.35%
Basis points, interest rate		1.80%
Maturity date of loan		Dec. 15, 2027
Wells Fargo Bank [Member]
Derivative [Line Items]
Loan amount	$ 115,300,000
Aareal Capital Corporation [Member]
Derivative [Line Items]
Loan amount	118,500,000
Available to draw	$ 3,380,000
Basis points, interest rate	2.85%
Maturity date of loan	Feb. 06, 2021
Grande Rotunda LLC [Member]
Derivative [Line Items]
Loan amount				$ 118,500,000
Interest rate cap				3.00%
Unrealized gain (loss) on derivatives				$ (160,000)	72,000
Interest rate cap asset				$ 0	$ 160,000
Basis points, interest rate				2.85%
Grande Rotunda LLC Loan [Member]
Derivative [Line Items]
Loan amount				$ 118,500,000
Notional amount of interest rate swap				$ 121,900,000
Interest rate cap				3.00%
Maturity date of cap				Mar. 05, 2020
Wayne PSC, LLC Loan [Member]
Derivative [Line Items]
Refinanced loan amount			$ 24,200,000
Loan amount			$ 25,800,000	$ 23,700,000
Notional amount of interest rate swap				23,800,000
Fixed interest rate			3.625%
Basis points, interest rate			2.20%
Maturity date of loan			Oct. 01, 2026
People's United Bank [Member]
Derivative [Line Items]
Loan amount				19,400,000
Notional amount of interest rate swap				$ 19,400,000
People's United Bank [Member] | Tranche One [Member]
Derivative [Line Items]
Fixed interest rate				3.81%
Basis points, interest rate				2.10%
Maturity date of loan				Jan. 03, 2023
People's United Bank [Member] | Tranche Two [Member]
Derivative [Line Items]
Fixed interest rate				3.53%
Regency Loan [Member]
Derivative [Line Items]
Refinanced loan amount				$ 16,200,000
Loan amount				15,600,000
Notional amount of interest rate swap				$ 15,600,000
Fixed interest rate				3.75%
Basis points, interest rate				1.25%
Maturity date of loan				Dec. 15, 2024