Debt instrument interest payment deferment period.

No definition available.

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Period Type:	duration

- Definition

Number Of Floating Rate Trust Preferred Securities

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Number Of Unsecured Lines Of Credit Issued

+ References

No definition available.

+ Details

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Namespace Prefix:	ccne_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 6
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109500613&loc=SL6036836-161870

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

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
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- 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

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of advances or credit lines available from the Federal Home Loan Bank (FHLB).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of maximum advances or credit lines available from the Federal Home Loan Bank (FHLB).

+ References

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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+ Details

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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- Details

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- Details

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- Details

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- Details

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Borrowings - Additional Information (Detail)	1 Months Ended	12 Months Ended
Borrowings - Additional Information (Detail)	Sep. 30, 2016 USD ($)	Dec. 31, 2018 USD ($) line_of_credit	Dec. 31, 2017 USD ($) line_of_credit	Dec. 31, 2007 USD ($) security
Debt Instrument [Line Items]
Remaining borrowing capacity		$ 317,570,000
Federal home loan balance		$ 769,316,000
Number of unsecured lines of credit issued \| line_of_credit		1	1
Pledge on certain loan amount		$ 10,000,000	$ 10,000,000
Line of credit, outstanding amount		$ 0	$ 0
Subordinated Debt
Debt Instrument [Line Items]
Number of preferred trust securities \| security				2
Floating rate trust preferred securities				$ 10,000,000
Effective percentage		4.36%	3.24%
Trust preferred securities, interest payment deferment period		5 years
Subordinated Debt \| LIBOR
Debt Instrument [Line Items]
Line of credit, basis spread on variable rate		1.55%
Notes Maturing In October 2026 \| Subordinated Debt
Debt Instrument [Line Items]
Floating rate trust preferred securities	$ 50,000,000
Interest rate, percentage	5.75%
Notes Maturing In October 2026 \| Subordinated Debt \| LIBOR
Debt Instrument [Line Items]
Line of credit, basis spread on variable rate	4.55%
Line of Credit \| Overnight Borrowing Agreements
Debt Instrument [Line Items]
Line of credit, outstanding amount		$ 0	$ 0