Loans (Loans Individually And Collectively Evaluated For Impairment) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
Mar. 31, 2015	Dec. 31, 2014
Financing Receivable, Impaired [Line Items]
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	$ 5,064	$ 3,660
Nonaccrual and accruing restructured loans	112,748	116,725
Nonaccrual and accruing restructured loans, loans individually evaluated for impairment	70,492	73,712
Nonaccrual and accruing restructured loans, loans collectively evaluated for impairment	42,256	43,013
Partial Charge-Offs On Impaired Loans	25,792prk_PartialChargeOffsOnImpairedLoans	32,480prk_PartialChargeOffsOnImpairedLoans
Commercial Financial And Agricultural [Member]
Financing Receivable, Impaired [Line Items]
Nonaccrual and accruing restructured loans	20,578	19,123
Nonaccrual and accruing restructured loans, loans individually evaluated for impairment	20,571	19,106
Nonaccrual and accruing restructured loans, loans collectively evaluated for impairment	7	17
Construction Real Estate, SEPH Commercial Land and Development [Member]
Financing Receivable, Impaired [Line Items]
Nonaccrual and accruing restructured loans	2,077	2,078
Nonaccrual and accruing restructured loans, loans individually evaluated for impairment	2,077	2,078
Construction Real Estate - Remaining Commercial [Member]
Financing Receivable, Impaired [Line Items]
Nonaccrual and accruing restructured loans	5,725	5,609
Nonaccrual and accruing restructured loans, loans individually evaluated for impairment	5,725	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	182	153
Nonaccrual and accruing restructured loans, loans individually evaluated for impairment	0	0
Nonaccrual and accruing restructured loans, loans collectively evaluated for impairment	182	153
Construction Real Estate - Installment [Member]
Financing Receivable, Impaired [Line Items]
Nonaccrual and accruing restructured loans	232	240
Nonaccrual and accruing restructured loans, loans individually evaluated for impairment	0	0
Nonaccrual and accruing restructured loans, loans collectively evaluated for impairment	232	240
Residential Real Estate - Commercial [Member]
Financing Receivable, Impaired [Line Items]
Nonaccrual and accruing restructured loans	25,219	24,930
Nonaccrual and accruing restructured loans, loans individually evaluated for impairment	25,219	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	31,954	32,218
Nonaccrual and accruing restructured loans, loans individually evaluated for impairment	0	0
Nonaccrual and accruing restructured loans, loans collectively evaluated for impairment	31,954	32,218
Residential Real Estate - HELOC [Member]
Financing Receivable, Impaired [Line Items]
Nonaccrual and accruing restructured loans	2,602	2,509
Nonaccrual and accruing restructured loans, loans individually evaluated for impairment	0	0
Nonaccrual and accruing restructured loans, loans collectively evaluated for impairment	2,602	2,509
Residential Real Estate - Installment [Member]
Financing Receivable, Impaired [Line Items]
Nonaccrual and accruing restructured loans	2,351	2,522
Nonaccrual and accruing restructured loans, loans individually evaluated for impairment	0	0
Nonaccrual and accruing restructured loans, loans collectively evaluated for impairment	2,351	2,522
Commercial Real Estate [Member]
Financing Receivable, Impaired [Line Items]
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	645	262
Nonaccrual and accruing restructured loans	16,900	21,989
Nonaccrual and accruing restructured loans, loans individually evaluated for impairment	16,900	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	4,928	5,354
Nonaccrual and accruing restructured loans, loans collectively evaluated for impairment	4,928	5,354
Financing Receivable With No Related Allowance Recorded [Member]
Financing Receivable, Impaired [Line Items]
Partial Charge-Offs On Impaired Loans	$ 21,600	$ 32,400

Financing receivable recorded investment nonaccrual and accruing restructured loans.

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- Definition

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

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

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+ References

No definition available.

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- 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=35738203&loc=SL6953423-111524

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