Subordinated Debentures - Additional Information (Detail) - Subordinated Debentures $ in Millions	12 Months Ended
Dec. 31, 2005 USD ($)
Subordinated Borrowing [Line Items]
Proceeds from Issuance of Subordinated Long-term Debt	$ 4.1
Debt Instrument Maturity Date Year	2035
Mandatorily redeemable debt securities	$ 4.1
Subordinated debenture variable interest rate	1.35%

Debt instrument maturity date year.

No definition available.

Name:	ubcp_DebtInstrumentMaturityDateYear
Namespace Prefix:	ubcp_
Data Type:	xbrli:gYearItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Amount of distributions during the period on mandatorily redeemable securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 480
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6402702&loc=d3e21951-110878

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The cash inflow from a borrowing where a lender is placed in a lien position behind debt having a higher priority of repayment (senior) in liquidation of the entity's assets or underlying collateral.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Financing Activities
-URI http://asc.fasb.org/extlink&oid=6513228

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3255-108585

+ Details

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Namespace Prefix:	us-gaap_
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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Balance Type:	na
Period Type:	duration

- Details

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Balance Type:
Period Type: