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The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=25495931&loc=d3e18845-111554

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Recorded Investment
-URI http://asc.fasb.org/extlink&oid=65880944

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Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and for which there was a payment default.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953682-111524

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Recorded investment in financing receivables that are on nonaccrual status as of the balance sheet date.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Recorded Investment
-URI http://asc.fasb.org/extlink&oid=65880944

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5111-111524

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Period Type:	instant

Reflects the amount of additional interest income that would have been recorded if impaired or nonperforming loans were instead current, in compliance with their original terms, and outstanding throughout the reporting period or since origination (if held for part of the period).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=25495931&loc=d3e18794-111554

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Data Type:	xbrli:monetaryItemType
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Period Type:	duration

Reflects the carrying amount of loans deemed to be questionable as to collection on which no interest is continuing to be recognized.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5111-111524

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Balance Type:	debit
Period Type:	instant

For an unclassified balance sheet, reflects the carrying amount of unpaid loan amounts due from related parties at the balance sheet date.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7(e))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 850
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864

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

Amount of cash inflow from related parties which reduce the amount of loans and leases receivable due from related parties.

Name:	us-gaap_LoansAndLeasesReceivableRelatedPartiesProceeds
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Represents the amount of financing receivable restructuring recorded investment restored to accrual status.

No definition available.

Name:	usbi_FinancingReceivableRestructuringRecordedInvestmentRestoredToAccrualStatus
Namespace Prefix:	usbi_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Represents the amount of financing receivable restructuring recorded investment with nonaccrual status.

No definition available.

Name:	usbi_FinancingReceivableRestructuringRecordedInvestmentWithNonaccrualStatus
Namespace Prefix:	usbi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

Interest income recorded.

No definition available.

Name:	usbi_InterestIncomeRecorded
Namespace Prefix:	usbi_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Represents the threshold used in determining which loans that have been modified in a troubled debt restructuring are considered impaired and evaluated individually for impairment. All such loans with a principal balance above this threshold are considered impaired and evaluated individually for impairment.

No definition available.

Name:	usbi_LoansModifiedInATroubledDebtRestructuringIndividuallyEvaluatedForImpairmentPrincipalBalanceThreshold
Namespace Prefix:	usbi_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Represents the minimum modified loan term period.

No definition available.

Name:	usbi_MinimumModifiedLoanTermPeriod
Namespace Prefix:	usbi_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

Indicates the number of loans made to related party during the period.

No definition available.

Name:	usbi_NumberOfLoansRelatedParty
Namespace Prefix:	usbi_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

Represents the number of portfolio segments into which the Company has divided the loan portfolio as of the balance sheet date.

No definition available.

Name:	usbi_NumberOfPortfolioSegments
Namespace Prefix:	usbi_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

Represents the percentage of the loan portfolio that is concentrated in a certain category.

No definition available.

Name:	usbi_PercentageOfLoanPortfolio
Namespace Prefix:	usbi_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

Represents the troubled debt restructuring modified period term.

No definition available.

Name:	usbi_TroubledDebtRestructuringModifiedPeriodTerm
Namespace Prefix:	usbi_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=usbi_RealEstate1Member
Namespace Prefix:
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Name:	us-gaap_RelatedPartyTransactionAxis=usbi_RelatedPartyLoanMember
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Data Type:	na
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Namespace Prefix:
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Period Type:

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=usbi_RestructuredLoansMember
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