Significant Accounting Policies (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014 Entity Branch Subsidiary	Dec. 31, 2013
PRINCIPLES OF CONSOLIDATION [Abstract]
Required ownership percentage for consolidation (in hundredths)	50.00%
Required ownership percentage for consolidation of directly or indirectly held subsidiaries, minimum (in hundredths)	20.00%
Required ownership percentage for consolidation of directly or indirectly held subsidiaries, maximum (in hundredths)	50.00%
NATURE OF OPERATIONS [Abstract]
Number of subsidiaries	2opof_NumberOfSubsidiaries
Number of branch offices	18opof_NumberOfBranchOffices
VARIABLE INTEREST ENTITIES [Abstract]
Number of consolidated variable interest entities	0
Number of variable interest entities not primary beneficiary	1
Concentration Risk [Line Items]
Total Loans	$ 535,994	$ 500,699
CASH AND CASH EQUIVALENTS [Abstract]
Maturity period of cash equivalents	90 days
INTEREST-BEARING DEPOSITS IN BANKS [Abstract]
Maturity period of interest bearing deposits	1 year
TROUBLED DEBT RESTRUCTURINGS [Abstract]
Loans classified as TDRs	12,318	12,091
INCOME TAXES [Abstract]
More likely than not percentage limit (in hundredths)	50.00%opof_MoreLikelyThanNotPercentageLimit
Tax benefit realization likelihood (in hundredths)	50.00%
Advertising Expense	265us-gaap_AdvertisingExpense	264us-gaap_AdvertisingExpense
Buildings and Equipment [Member] \| Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	3 years
Buildings and Equipment [Member] \| Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	39 years
Software [Member] \| Minimum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	3 years
Software [Member] \| Maximum [Member]
Property, Plant and Equipment [Line Items]
Estimated useful lives	5 years
Commercial and construction real estate [Member]
Concentration Risk [Line Items]
Total Loans	$ 296,613	$ 301,576
Percentage of total loans (in hundredths)	55.34%	60.23%

Amount of investment in financing receivables modified by troubled debt restructurings.

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Maturity period of balances due from banks and federal funds sold.

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Maturity period of interest bearing deposits, which are carried at cost.

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Minimum likelihood percentage which is more than 50 percent.

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Number of branch offices operated by the entity.

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Number of primary beneficial variable interest entities that are consolidated during the period.

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Number of operating subsidiaries held by the entity.

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Number of non-primary beneficial variable interest entities that are not consolidated during the period.

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Percentage of total loans concentrated in commercial real estate.

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Percentage of tax benefit realization likelihood upon settlement with taxing authority.

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Required ownership percentage of voting rights to be in directly or indirectly held subsidiaries for consolidation. The entity owns required the voting rights or it exercises control.

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Maximum ownership percentage of voting rights to held under equity method investment in subsidiaries for consolidation. The entity owns required the voting rights or has the ability to exercise significant influence or both.

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Minimum ownership percentage of voting rights to held under equity method investment in subsidiaries for consolidation. The entity owns required the voting rights or has the ability to exercise significant influence or both.

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- Definition

Amount charged to advertising expense for the period, which are expenses incurred with the objective of increasing revenue for a specified brand, product or product line.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 720

-SubTopic 35

-Section 50

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

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-Name Accounting Standards Codification

-Topic 310

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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