Cash outflow related to parent making additional equity contribution to an consolidated subsidiary which it controls

No definition available.

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Number of real estate joint venture investments.

+ References

No definition available.

+ Details

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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

The percentage of ownership of common stock or equity participation in a consolidated joint venture investee

+ References

No definition available.

+ Details

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Data Type:	dtr-types:percentItemType
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- Definition

The ownership interest of parent of consolidated joint venture after noncontrolling interest redemption

+ References

No definition available.

+ Details

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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Change in value of redeemable non controlling interest during period

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

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

+ References

No definition available.

+ Details

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Namespace Prefix:	uba_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

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

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

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.

+ References

No definition available.

+ Details

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=120321790&loc=d3e6927-128479

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3213-108585

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Balance Type:	credit
Period Type:	duration

- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3213-108585

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Balance Type:	credit
Period Type:	duration

- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 480
-SubTopic 10
-Section S99
-Paragraph 3A
-Subparagraph (16)(c)
-URI http://asc.fasb.org/extlink&oid=122040564&loc=SL6540498-122764

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-Topic 480
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-Section S99
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 480
-SubTopic 10
-Section S99
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-URI http://asc.fasb.org/extlink&oid=122040564&loc=SL6540498-122764

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 480
-SubTopic 10
-Section S99
-Paragraph 3A
-Subparagraph 14
-URI http://asc.fasb.org/extlink&oid=122040564&loc=SL6540498-122764

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

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- Details

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- Details

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- Details

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CONSOLIDATED JOINT VENTURES AND REDEEMABLE NONCONTROLLING INTERESTS (Details)	6 Months Ended		12 Months Ended
	Apr. 30, 2022 USD ($) Investment Property shares	Apr. 30, 2021 USD ($)	Oct. 31, 2021 USD ($)	Mar. 28, 2012
Business Acquisition [Line Items]
Number of real estate joint venture investments \| Investment	4
Number of commercial real estate properties owned \| Property	77
Redeemable non-controlling interests [Roll Forward]
Beginning Balance	$ 67,395,000	$ 62,071,000	$ 62,071,000
Change in Redemption Value	(1,629,000)	$ 8,600,000	10,450,000
Redemption Value of UB High Ridge non-controlling interest	(1,358,000)		(5,126,000)
uba_ Redemption Value Of UB New City, LLC Non Controlling Interest	(502,000)		0
Ending Balance	$ 63,906,000		$ 67,395,000
UB Orangeburg, LLC [Member]
Business Acquisition [Line Items]
Ownership interest	43.80%			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	26.90%
Fixed annual distribution	5.36%
Additional investment in consolidated joint venture	$ 9,700,000
Additional Equity Contributed to Joint Venture	1,500,000
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]
Ownership interest	84.30%
Percentage Ownership of Consolidated Joint Venture after Redemption	100.00%
Additional investment in consolidated joint venture	$ 502,000