Name:	opof_ConsumerLoansClassifiedAsLossPastDueThreshold
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- References

No definition available.

Name:	opof_LoansInNonaccrualStatusByClassOfLoanAbstract
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The past due period of time commercial and industrial loans (including construction loans and commercial loans secured and not secured by real estate) in nonaccrual status when the full and timely collection of interest or principal becomes uncertain, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

Name:	opof_NonAccrualStatusCommercialAndIndustrialLoansPastDueThreshold
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Data Type:	xbrli:durationItemType
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The past due period of time consumer loans not secured by real estate will generally be placed in nonaccrual status, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

Name:	opof_NonaccrualStatusConsumerLoansNotSecuredByRealEstatePastDueThreshold
Namespace Prefix:	opof_
Data Type:	xbrli:durationItemType
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The past due period of time consumer loans secured by real estate are placed in nonaccrual status, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

Name:	opof_NonaccrualStatusConsumerLoansSecuredByRealEstatePastDueThreshold
Namespace Prefix:	opof_
Data Type:	xbrli:durationItemType
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The period nonaccrual status loans are returned to accrual status when all the principal and interest amounts contractually due are brought current and future payments are reasonably assured, or when the borrower has resumed paying the full amount of the scheduled contractual interest and principal payments, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

No definition available.

Name:	opof_NonaccrualStatusReturnToAccrualStatusThreshold
Namespace Prefix:	opof_
Data Type:	xbrli:durationItemType
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Amortized cost of financing receivable on nonaccrual status. Excludes net investment in lease.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=123577603&loc=d3e5111-111524

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 20
-Section 50
-Paragraph 16
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=124255953&loc=SL82919258-210447

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph (a)
-Subparagraph (3)

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher SEC
-Name Regulation S-K (SK)
-Number 229
-Section 1405
-Paragraph (a)
-Subparagraph (2)

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Balance Type:	debit
Period Type:	instant

- References

No definition available.

Name:	us-gaap_LoanAndLeaseReceivablesImpairedAbstract
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The amount of interest income on impaired and nonperforming loans that is due to the change in present value attributable to the passage of time.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 19
-URI https://asc.fasb.org/extlink&oid=123577603&loc=d3e5278-111524

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

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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 1
-URI https://asc.fasb.org/extlink&oid=121585226&loc=d3e18794-111554

Name:	us-gaap_LoansAndLeasesReceivableImpairedInterestLostOnNonaccrualLoans
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

The gross interest income that would have been recorded in the period on troubled debt restructurings, if the loans had been current in accordance with their original terms and had been outstanding throughout the period or since origination, if held for part of the period.

Name:	us-gaap_LoansAndLeasesReceivableImpairedTroubledDebtInterestIncome
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Name:	srt_RangeAxis=srt_MinimumMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=opof_RealEstatePortfolioSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=opof_OneToFourFamilyResidentialMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=opof_CommercialNonOwnerOccupiedMember
Namespace Prefix:
Data Type:	na
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Period Type:

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=opof_ConstructionAndLandDevelopmentLoansMember
Namespace Prefix:
Data Type:	na
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