Percentage of invested capital non-managing members receive in a fixed annual cash distribution.

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Number of properties the Company owned or had equity interest in.

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Number of real estate joint venture investments.

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Number of shares of common stock included in the calculation of a regular quarterly cash distribution equivalent to annual cash distribution to non-managing member of the subsidiary company pursuant to the operating agreement.

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No definition available.

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Change in value of redeemable non controlling interest during period

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The redemption value of the minority entities equity for a consolidated investment by the parent.

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The redemption value of the minority entities equity for a consolidated investment by the parent.

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The redemption value of the minority entities equity for a consolidated investment by the parent.

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The redemption value of the minority entities equity for a consolidated investment by the parent.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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The cash outflow associated with the investment in or advances to an entity in which the reporting entity shares control of the entity with another party or group.

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As of the reporting date, the aggregate carrying amount of all noncontrolling interests which are redeemable by the (parent) entity (1) at a fixed or determinable price on a fixed or determinable date, (2) at the option of the holder of the noncontrolling interest, or (3) upon occurrence of an event that is not solely within the control of the (parent) entity. This item includes noncontrolling interest holder's ownership (or holders' ownership) regardless of the type of equity interest (common, preferred, other) including all potential organizational (legal) forms of the investee entity.

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CONSOLIDATED JOINT VENTURES AND REDEEMABLE NONCONTROLLING INTERESTS (Details)	6 Months Ended		12 Months Ended
	Apr. 30, 2020 USD ($) Property Investment shares	Apr. 30, 2019 USD ($)	Oct. 31, 2019 USD ($)	Mar. 28, 2012
Business Acquisition [Line Items]
Number of real estate joint venture investments \| Investment	5
Number of commercial real estate properties owned \| Property	81
Redeemable non-controlling interests [Roll Forward]
Beginning Balance	$ 77,876,000	$ 78,258,000	$ 78,258,000
Change in Redemption Value	(11,009,000)	$ 1,400,000	4,452,000
Redemption Value of UB High Ridge non-controlling interest	(560,000)		(1,413,000)
Redemption Value of UB Dumont I, LLC non-controlling interest	0		(630,000)
uba_ Redemption Value Of UB New City, LLC Non Controlling Interest	(50,000)		(91,000)
Redemption Value of UB Ironbound, LP non-controlling interest	0		(2,700,000)
Ending Balance	$ 66,257,000		$ 77,876,000
UB Orangeburg, LLC [Member]
Business Acquisition [Line Items]
Ownership interest	44.60%			2.92%
Additional investment in consolidated joint venture	$ 6,500,000
UB Orangeburg, LLC [Member] \| Class A Common Stock [Member]
Business Acquisition [Line Items]
Number of shares of common stock included in calculation of regular quarterly cash distribution equivalent to annual cash distribution to non-managing member of subsidiary (in shares) \| shares	1
McLean Plaza Associates, LLC [Member]
Business Acquisition [Line Items]
Ownership interest	53.00%
Fixed annual distribution	5.05%
UB High Ridge, LLC [Member]
Business Acquisition [Line Items]
Number of commercial real estate properties owned \| Property	3
Cost of acquisition	$ 5,500,000
Ownership interest	14.20%
Fixed annual distribution	5.50%
Additional investment in consolidated joint venture	$ 3,200,000
UB Dumont I, LLC [Member]
Business Acquisition [Line Items]
Cost of acquisition	$ 3,900,000
Ownership interest	36.40%
Fixed annual distribution	5.10%
Additional investment in consolidated joint venture	$ 630,000
UB New City I, LLC [Member]
Business Acquisition [Line Items]
Cost of acquisition	$ 2,400,000
Ownership interest	79.70%
Fixed annual distribution	5.00%
Additional investment in consolidated joint venture	$ 141,000