Loans (Loans Individually And Collectively Evaluated For Impairment) (Details) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2015	Dec. 31, 2014
Financing Receivable, Impaired [Line Items]
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	$ 6,597	$ 3,660
Nonaccrual and accruing restructured loans	112,335	116,725
Nonaccrual and accruing restructured loans, loans individually evaluated for impairment	70,596	73,712
Nonaccrual and accruing restructured loans, loans collectively evaluated for impairment	41,739	43,013
Partial Charge-Offs On Impaired Loans	30,024	32,480
Commercial Financial And Agricultural [Member]
Financing Receivable, Impaired [Line Items]
Nonaccrual and accruing restructured loans	20,431	19,123
Nonaccrual and accruing restructured loans, loans individually evaluated for impairment	20,429	19,106
Nonaccrual and accruing restructured loans, loans collectively evaluated for impairment	2	17
Construction Real Estate, SEPH Commercial Land and Development [Member]
Financing Receivable, Impaired [Line Items]
Nonaccrual and accruing restructured loans	2,047	2,078
Nonaccrual and accruing restructured loans, loans individually evaluated for impairment	2,047	2,078
Construction Real Estate - Remaining Commercial [Member]
Financing Receivable, Impaired [Line Items]
Nonaccrual and accruing restructured loans	6,032	5,609
Nonaccrual and accruing restructured loans, loans individually evaluated for impairment	6,032	5,609
Nonaccrual and accruing restructured loans, loans collectively evaluated for impairment	0	0
Construction Real Estate - Mortgage [Member]
Financing Receivable, Impaired [Line Items]
Nonaccrual and accruing restructured loans	120	153
Nonaccrual and accruing restructured loans, loans individually evaluated for impairment	0	0
Nonaccrual and accruing restructured loans, loans collectively evaluated for impairment	120	153
Construction Real Estate - Installment [Member]
Financing Receivable, Impaired [Line Items]
Nonaccrual and accruing restructured loans	246	240
Nonaccrual and accruing restructured loans, loans individually evaluated for impairment	0	0
Nonaccrual and accruing restructured loans, loans collectively evaluated for impairment	246	240
Residential Real Estate - Commercial [Member]
Financing Receivable, Impaired [Line Items]
Nonaccrual and accruing restructured loans	24,441	24,930
Nonaccrual and accruing restructured loans, loans individually evaluated for impairment	24,441	24,930
Nonaccrual and accruing restructured loans, loans collectively evaluated for impairment	0	0
Residential Real Estate - Mortgage [Member]
Financing Receivable, Impaired [Line Items]
Nonaccrual and accruing restructured loans	31,761	32,218
Nonaccrual and accruing restructured loans, loans individually evaluated for impairment	0	0
Nonaccrual and accruing restructured loans, loans collectively evaluated for impairment	31,761	32,218
Residential Real Estate - HELOC [Member]
Financing Receivable, Impaired [Line Items]
Nonaccrual and accruing restructured loans	2,376	2,509
Nonaccrual and accruing restructured loans, loans individually evaluated for impairment	0	0
Nonaccrual and accruing restructured loans, loans collectively evaluated for impairment	2,376	2,509
Residential Real Estate - Installment [Member]
Financing Receivable, Impaired [Line Items]
Nonaccrual and accruing restructured loans	2,410	2,522
Nonaccrual and accruing restructured loans, loans individually evaluated for impairment	0	0
Nonaccrual and accruing restructured loans, loans collectively evaluated for impairment	2,410	2,522
Commercial Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	688	262
Nonaccrual and accruing restructured loans	17,647	21,989
Nonaccrual and accruing restructured loans, loans individually evaluated for impairment	17,647	21,989
Nonaccrual and accruing restructured loans, loans collectively evaluated for impairment	0	0
Consumer [Member]
Financing Receivable, Impaired [Line Items]
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	0	0
Nonaccrual and accruing restructured loans	4,824	5,354
Nonaccrual and accruing restructured loans, loans collectively evaluated for impairment	4,824	5,354
Financing Receivable With No Related Allowance Recorded [Member]
Financing Receivable, Impaired [Line Items]
Partial Charge-Offs On Impaired Loans	$ 25,500	$ 32,400

Financing receivable recorded investment nonaccrual and accruing restructured loans.

No definition available.

Name:	prk_FinancingReceivableRecordedInvestmentNonaccrualAndAccruingRestructuredLoans
Namespace Prefix:	prk_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Financing Receivable Recorded Investment Nonaccrual And Accruing Restructured Loans, Collectively Evaluated for Impairment

+ References

No definition available.

+ Details

Name:	prk_FinancingReceivableRecordedInvestmentNonaccrualAndAccruingRestructuredLoansCollectivelyEvaluatedForImpairment
Namespace Prefix:	prk_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Financing Receivable Recorded Investment Nonaccrual And Accruing Restructured Loans, Individually Evaluated for Impairment

+ References

No definition available.

+ Details

Name:	prk_FinancingReceivableRecordedInvestmentNonaccrualAndAccruingRestructuredLoansIndividuallyEvaluatedForImpairment
Namespace Prefix:	prk_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Partial Charge-Offs On Impaired Loans

+ References

No definition available.

+ Details

Name:	prk_PartialChargeOffsOnImpairedLoans
Namespace Prefix:	prk_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-Subparagraph (g)

-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953423-111524

+ Details

Name:	us-gaap_FinancingReceivableAllowanceForCreditLossesIndividuallyEvaluatedForImpairment1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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

Name:	us-gaap_FinancingReceivableImpairedLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis=prk_CommercialFinancialAndAgriculturalMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis=prk_ConstructionRealEstateSephCommercialLandAndDevelopmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis=prk_ConstructionRealEstateRemainingCommercialMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis=prk_ConstructionRealEstateMortgageMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis=prk_ConstructionRealEstateInstallmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis=prk_ResidentialRealEstateCommercialMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis=prk_ResidentialRealEstateMortgageMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis=prk_ResidentialRealEstateHomeEquityLineOfCreditMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis=prk_ResidentialRealEstateInstallmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

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

- Details

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

- Details

Name:	us-gaap_ClassOfFinancingReceivableTypeOfBorrowerAxis=prk_FinancingReceivableWithNoRelatedAllowanceRecordedMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: