Fair Value (Reconciliation Of The Level 3 Input For Financial Instruments Measured On A Recurring Basis) (Details) (USD $) In Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2011	Jun. 30, 2010	Jun. 30, 2011	Jun. 30, 2010
Obligations Of States And Political Subdivisions [Member]
Balance, beginning	$ 2,470	$ 2,744	$ 2,598	$ 2,751
Total gains/(losses), Included in earnings - realized
Total gains/(losses), Included in earnings - unrealized			(128)
Total gains/(losses), Included in other comprehensive income		12		5
Total gains/(losses), Purchases, sales, issuances and settlements, other, net	(2,470)		(2,470)
Balance, ending	0	2,756	0	2,756
Equity Securities [Member]
Balance, beginning	740		745
Total gains/(losses), Included in earnings - realized
Total gains/(losses), Included in earnings - unrealized
Total gains/(losses), Included in other comprehensive income	1		(4)
Total gains/(losses), Purchases, sales, issuances and settlements, other, net
Balance, ending	741		741
Fair Value Swap [Member]
Balance, beginning	(60)	(500)	(60)	(500)
Total gains/(losses), Included in earnings - realized
Total gains/(losses), Included in earnings - unrealized
Total gains/(losses), Included in other comprehensive income
Total gains/(losses), Purchases, sales, issuances and settlements, other, net	(140)	160	(140)	160
Balance, ending	$ (200)	$ (340)	$ (200)	$ (340)

Fair Value Asset And Liabilities Measured On Recurring Basis Realized Gain Loss Included In Earnings

Name:	prk_FairValueAssetAndLiabilitiesMeasuredOnRecurringBasisRealizedGainLossIncludedInEarnings
Namespace Prefix:	prk
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Fair Value Asset And Liabilities Measured On Recurring Basis Unrealized Gain Loss Included In Earnings

+ Details

Name:	prk_FairValueAssetAndLiabilitiesMeasuredOnRecurringBasisUnrealizedGainLossIncludedInEarnings
Namespace Prefix:	prk
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

This element represents total gains (losses) for the period (realized and unrealized), arising from assets and liabilities measured at fair value on a recurring basis using unobservable inputs (Level 3), which are included in other comprehensive income (a separate component of shareholders' equity).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
-SubTopic 10
-Topic 820
-URI http://asc.fasb.org/extlink&oid=6925170&loc=d3e19207-110258

+ Details

Name:	us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetAndLiabilityGainLossIncludedInOtherComprehensiveIncomeLoss
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

This element represents purchases, sales, issuances, and settlements (net) which have taken place during the period in relation to assets measured at fair value on a recurring basis using unobservable inputs (Level 3).

+ References

+ Details

Name:	us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetPurchasesSalesIssuancesSettlements
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

This element represents an asset measured at fair value using significant unobservable inputs (Level 3) which is required for reconciliation purposes of beginning and ending balances.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Statement of Financial Accounting Standard (FAS)
-Number 157
-Paragraph 32
-Subparagraph c
-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=6925170&loc=d3e19207-110258

+ Details

Name:	us-gaap_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetValue
Namespace Prefix:	us-gaap
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant