Commercial industrial and agricultural loan amount as maximum percentage of accounts receivable.

No definition available.

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Period Type:	duration

- Definition

Commercial industrial and agricultural loan amount as maximum percentage of business equipment.

+ References

No definition available.

+ Details

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Namespace Prefix:	ccne_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Commercial industrial and agricultural loan amount as maximum percentage of business inventory.

+ References

No definition available.

+ Details

Name:	ccne_CommercialIndustrialAndAgriculturalLoanAmountAsMaximumPercentageOfBusinessInventory
Namespace Prefix:	ccne_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Commercial mortgage loan amount as maximum percentage of appraised real estate value.

+ References

No definition available.

+ Details

Name:	ccne_CommercialMortgageLoanAmountAsMaximumPercentageOfAppraisedRealEstateValue
Namespace Prefix:	ccne_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Minimum period to be considered for loan to have defaulted.

+ References

No definition available.

+ Details

Name:	ccne_MinimumPeriodToBeConsideredForLoanToHaveDefaulted
Namespace Prefix:	ccne_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Outstanding balance of annual loans.

+ References

No definition available.

+ Details

Name:	ccne_OutStandingBalanceOfAnnualLoans
Namespace Prefix:	ccne_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Outstanding balance of semi annual loans.

+ References

No definition available.

+ Details

Name:	ccne_OutstandingBalanceOfSemiAnnualLoans
Namespace Prefix:	ccne_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage of commercial industrial and agricultural loans in loan portfolio.

+ References

No definition available.

+ Details

Name:	ccne_PercentageOfCommercialIndustrialAndAgriculturalLoansInLoanPortfolio
Namespace Prefix:	ccne_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Percentage of commercial mortgage loans in loan portfolio.

+ References

No definition available.

+ Details

Name:	ccne_PercentageOfCommercialMortgageLoansInLoanPortfolio
Namespace Prefix:	ccne_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Percentage of consumer loans and credit card products in loan portfolio.

+ References

No definition available.

+ Details

Name:	ccne_PercentageOfConsumerLoansAndCreditCardProductsInLoanPortfolio
Namespace Prefix:	ccne_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Percentage of residential real estate loans in loan portfolio.

+ References

No definition available.

+ Details

Name:	ccne_PercentageOfResidentialRealEstateLoansInLoanPortfolio
Namespace Prefix:	ccne_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Troubled debt restructuring loan principal balance forgiven.

+ References

No definition available.

+ Details

Name:	ccne_TroubledDebtRestructuringLoanPrincipalBalanceForgiven
Namespace Prefix:	ccne_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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_AccountsNotesAndLoansReceivableLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953676-111524

+ Details

Name:	us-gaap_FinancingReceivableModificationsNumberOfContracts2
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of deferred fees paid by borrowers and unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of loans that are being amortized into income as an adjustment to yield. Excludes amounts for loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6378536&loc=d3e10092-111533

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

Name:	us-gaap_TroubledDebtRestructuringDebtorSubsequentPeriodsAxis=ccne_TroubleDebtRestructuringMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=us-gaap_MaximumMember
Namespace Prefix:
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Loans - Additional Information (Detail)	3 Months Ended		12 Months Ended
Loans - Additional Information (Detail)	Mar. 31, 2017 USD ($) Loans	Mar. 31, 2016 Loans	Dec. 31, 2016 USD ($) Loans	Dec. 31, 2015 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Net unamortized loan (fees) costs \| $	$ (1,753,000)		$ (1,507,000)
Percentage of comprised loan, commercial, industrial and agricultural loans	31.00%		30.00%
Percentage of comprised loan, commercial mortgage loans	31.00%		31.00%
Percentage of loan-to-value to business equipment	80.00%
Percentage of loan-to-value to accounts receivable	75.00%
Percentage of loan-to-value to business inventory	60.00%
Percentage of loan-to-value to real estate	85.00%
Percentage of residential real estate loan in portfolio	35.00%		35.00%
Number of Loans \| Loans	15		15
Minimum period to be considered for loan to have defaulted	90 days
Principal balances forgiven in connection with loan restructuring \| $	$ 0			$ 0
Outstanding balance of semi annual loans	Greater than $1 million
Outstanding balance of annual loans	Less than $1 million
Trouble Debt Restructuring [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Loans \| Loans	0	0
Maximum [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Maximum percentage of consumer loan and credit card in portfolio	10.00%		10.00%