Fair Value (Fair Value Of Financial Instruments) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and money market instruments	$ 580,485	$ 237,699
Investment securities	1,401,895us-gaap_InvestmentOwnedAtFairValue	1,445,405us-gaap_InvestmentOwnedAtFairValue
Loans Held-for-sale, Fair Value Disclosure	7,987	5,264
Impaired loans carried at fair value	9,295prk_ImpairedLoanFairValue	16,963prk_ImpairedLoanFairValue
Other loans	4,775,046us-gaap_OtherAssetsFairValueDisclosure	4,757,461us-gaap_OtherAssetsFairValueDisclosure
Loans receivable, net	4,792,517	4,779,758
Noninterest bearing checking accounts	1,262,442	1,269,296
Interest bearing transactions accounts	1,311,827	1,122,079
Savings accounts	1,558,128	1,325,445
Time deposits	1,392,772prk_TimeDepositsFairValue	1,422,885prk_TimeDepositsFairValue
Other	2,700	1,269
Total deposits	5,527,869us-gaap_DepositsFairValueDisclosure	5,140,974us-gaap_DepositsFairValueDisclosure
Short-term borrowings	239,961prk_ShortTermBorrowingsFairValue	276,980prk_ShortTermBorrowingsFairValue
Long-term debt	778,231us-gaap_LongTermDebtFairValue	827,500us-gaap_LongTermDebtFairValue
Subordinated debentures/notes	43,421	42,995
Fair Value Swap [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Swap	226	226
Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Accrued interest receivable	4,313	4,048
Loans [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Accrued interest receivable	13,666	13,629
Deposits [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Accrued interest payable	1,136	1,125
Borrowings [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Accrued interest payable	1,452	1,426
Reported Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and money market instruments	580,485	237,699
Investment securities	1,398,860	1,442,477
Loans Held-for-sale, Fair Value Disclosure	7,987	5,264
Derivative Assets	189	70
Impaired loans carried at fair value	9,295	16,963
Other loans	4,757,951	4,753,033
Loans receivable, net	4,775,422	4,775,330
Noninterest bearing checking accounts	1,262,442	1,269,296
Interest bearing transactions accounts	1,311,827	1,122,079
Savings accounts	1,558,128	1,325,445
Time deposits	1,380,750	1,409,911
Other	2,700	1,269
Total deposits	5,515,847	5,128,000
Short-term borrowings	239,961	276,980
Long-term debt	733,555	786,602
Subordinated debentures/notes	45,000	45,000
Reported Value Measurement [Member] \| Fair Value Swap [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Swap	226	226
Reported Value Measurement [Member] \| Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Accrued interest receivable	4,313	4,048
Reported Value Measurement [Member] \| Loans [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Accrued interest receivable	13,666	13,629
Reported Value Measurement [Member] \| Deposits [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Accrued interest payable	1,136	1,125
Reported Value Measurement [Member] \| Borrowings [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Accrued interest payable	1,452	1,426
Fair Value, Inputs, Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash and money market instruments	580,485	237,699
Investment securities	1,891	1,922
Derivative Assets	0	0
Noninterest bearing checking accounts	1,262,442	1,269,296
Interest bearing transactions accounts	1,311,827	1,122,079
Savings accounts	1,558,128	1,325,445
Other	2,700	1,269
Total deposits	4,135,097	3,718,089
Fair Value, Inputs, Level 1 [Member] \| Deposits [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Accrued interest payable	14	14
Fair Value, Inputs, Level 1 [Member] \| Borrowings [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Accrued interest payable	7	3
Estimate of Fair Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Assets	189	70
Impaired loans carried at fair value		16,963
Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities	1,399,265	1,442,708
Loans Held-for-sale, Fair Value Disclosure	7,987	5,264
Derivative Assets	189	70
Loans receivable, net	8,176	5,334
Time deposits	1,392,772	1,422,885
Total deposits	1,392,772	1,422,885
Short-term borrowings	239,961	276,980
Long-term debt	778,231	827,500
Subordinated debentures/notes	43,421	42,995
Level 2 [Member] \| Securities [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Accrued interest receivable	4,313	4,048
Level 2 [Member] \| Deposits [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Accrued interest payable	1,122	1,111
Level 2 [Member] \| Borrowings [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Accrued interest payable	1,445	1,423
Fair Value, Inputs, Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Investment securities	739	775
Derivative Assets	0	0
Impaired loans carried at fair value	9,295	16,963
Other loans	4,775,046	4,757,461
Loans receivable, net	4,784,341	4,774,424
Fair Value, Inputs, Level 3 [Member] \| Fair Value Swap [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Swap	226	226
Fair Value, Inputs, Level 3 [Member] \| Loans [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Accrued interest receivable	$ 13,666	$ 13,629

Accrued Interest Receivable At Fair Value

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- Definition

Impaired Loan Fair Value

+ References

No definition available.

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- Definition

Interest Bearing Deposit Liabilities Fair Value

+ References

No definition available.

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- Definition

Interest Bearing Domestic Deposit Savings Fair Value

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No definition available.

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- Definition

Noninterest Bearing Deposit Liabilities Fair Value

+ References

No definition available.

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- Definition

Short Term Borrowings Fair Value

+ References

No definition available.

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- Definition

Time Deposits Fair Value

+ References

No definition available.

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- Definition

Fair value portion of accrued expenses.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 20

-Article 5

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.20)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Cash

-URI http://asc.fasb.org/extlink&oid=6506951

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-Publisher FASB

-Name Accounting Standards Codification

-Glossary Cash Equivalents

-URI http://asc.fasb.org/extlink&oid=6507016

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- Definition

Fair value portion of deposit liabilities held by the entity, including, but not limited to, foreign and domestic, interest and noninterest bearing, demand deposits, saving deposits, negotiable orders of withdrawal (NOW) and time deposits.

+ References

No definition available.

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- Definition

Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 825

-SubTopic 10

-Section 50

-Paragraph 10

-Subparagraph (a)

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-Topic 210

-SubTopic 20

-Section 55

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-URI http://asc.fasb.org/extlink&oid=36459792&loc=SL20226008-175313

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- Definition

Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

+ References

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- Definition

Fair value of subordinated debt obligations including, but not limited to, subordinated loan, subordinated bond, subordinated debenture or junior debt.

+ References

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (a),(b)

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- Definition

Value of the investment at close of period. For schedules of investments that are categorized, the value would be aggregated by category. For investment in and advances to affiliates, if operations of any controlled companies are different in character from those of the company, group such affiliates within divisions and by type of activities.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

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-Topic 946

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-Number 210

-Section 12C

-Paragraph Column C

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- Definition

Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

+ References

No definition available.

+ Details

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- Definition

Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Glossary Loan

-URI http://asc.fasb.org/extlink&oid=6517073

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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

+ Details

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- Definition

Fair value portion of other assets.

+ References

No definition available.

+ Details

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- Definition

Fair value portion of other liabilities.

+ References

No definition available.

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