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Approximate number of tenants in our consolidated portfolio

No definition available.

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Dollar value of base rent abatements entered into with tenants as of the balance sheet date

No definition available.

Name:	uba_DollarValueOfBaseRentAbatements
Namespace Prefix:	uba_
Data Type:	xbrli:monetaryItemType
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Dollar value of base rent abatements entered into with tenants after the balance sheet date.

No definition available.

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Namespace Prefix:	uba_
Data Type:	xbrli:monetaryItemType
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Dollar value of base rent deferrals entered into by the company with its tenants as of the balance sheet date

No definition available.

Name:	uba_DollarValueOfBaseRentDeferrals
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Dollar value of base rent deferrals entered into by the company with its tenants subsequent to balance sheet date

No definition available.

Name:	uba_DollarValueOfBaseRentDeferralsAfterQuarterEnd
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The number of lease modifications completed.

No definition available.

Name:	uba_NumberOfLeaseModificationsCompleted
Namespace Prefix:	uba_
Data Type:	xbrli:integerItemType
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Number of tenants requesting rent relief as a result of COVID-19 pandemic

No definition available.

Name:	uba_NumberOfRentReliefRequestsReceivedByCompany
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Data Type:	xbrli:integerItemType
Balance Type:	na
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Number of tenants withdrawing rent concession request.

No definition available.

Name:	uba_NumberOfTenantsWithdrawingRentConcessionRequest
Namespace Prefix:	uba_
Data Type:	xbrli:integerItemType
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Percent of annualized base rent for tenants requesting rent relief

No definition available.

Name:	uba_PercentOfAnnualizedBaseRentForTenantsRequestingRentRelief
Namespace Prefix:	uba_
Data Type:	num:percentItemType
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Number of base rent lease modifications entered into subsequent to balance sheet date

No definition available.

Name:	uba_RentModificationsCompletedSubsequentToBalanceSheetDate
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Data Type:	xbrli:integerItemType
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Reversal of previously billed lease income for tenants whose collectability assessment was changed from probable to not probable

No definition available.

Name:	uba_ReversalOfPreviouslyBilledLeaseIncome
Namespace Prefix:	uba_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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Square feet of spaced occupied by tenants requesting rent relief

No definition available.

Name:	uba_SquareFeetOfSpacedOccupiedByTenantsRequestingRentRelief
Namespace Prefix:	uba_
Data Type:	xbrli:integerItemType
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Period Type:	duration

Number of tenants in the company's portfolio who are being accounted for on a cash basis as a result of a not probable of collection assessmetn

No definition available.

Name:	uba_Tenantswithrevenuerecognizedonacashbasismethod
Namespace Prefix:	uba_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

Total provision for uncollectable accounts related to effect of COVID-19

No definition available.

Name:	uba_TotalCollectabilityAdjustment
Namespace Prefix:	uba_
Data Type:	xbrli:monetaryItemType
Balance Type:	na
Period Type:	duration

- References

No definition available.

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The valuation allowance as of the balance sheet date to reduce the gross amount of receivables to estimated net realizable value, which would be presented in parentheses on the face of the balance sheet.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=121611835&loc=d3e5074-111524

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The cumulative difference between the rental payments required by a lease agreement and the rental income or expense recognized on a straight-line basis, or other systematic and rational basis more representative of the time pattern in which use or benefit is granted or derived from the leased property, expected to be recognized in income or expense over the term of the leased property, by the lessor or lessee, respectively. Such receivable is reduced by allowances attributable to, for instance, credit risk associated with a lessee.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 35
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=121598990&loc=d3e40879-112712

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 25
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=121549951&loc=d3e39896-112707

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
-Section 25
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=121549951&loc=d3e39927-112707

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.8)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant

Amount of the adjustment to rental revenues to measure escalating leasing revenues on a straight line basis.

No definition available.