Deferred Compensation Plans - Additional Information (Detail)	12 Months Ended
Dec. 31, 2018
Postemployment Benefits [Abstract]
Maximum period for deferred compensation plan payment after individual's termination of service	10 years

Amount of fees or compensation deferred plus gains or net of losses over maximum period.

No definition available.

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