Name:	cznc_ContractualMaturitiesTimeDepositsAtOrAboveFDICInsuranceLimitAfter3Years
Namespace Prefix:	cznc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Amount of time deposit liabilities, including certificates of deposit, in denominations of $250,000 or more, maturing within one to three years after the balance sheet date.

No definition available.

Name:	cznc_ContractualMaturitiesTimeDepositsAtOrAboveFDICInsuranceLimitSixMonthsThrough12Months
Namespace Prefix:	cznc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Amount of time deposit liabilities, including certificates of deposit, in denominations of $250,000 or more, maturing within three months or fewer from the balance sheet date.

No definition available.

Name:	cznc_ContractualMaturitiesTimeDepositsAtOrAboveFDICInsuranceLimitThreeMonthsOrLess
Namespace Prefix:	cznc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Amount of time deposit liabilities, including certificates of deposit, in denominations of $250,000 or more, maturing within three to twelve months after the balance sheet date.

No definition available.

Name:	cznc_ContractualMaturitiesTimeDepositsAtOrAboveFDICInsuranceLimitThreeMonthsThroughTwelveMonths
Namespace Prefix:	cznc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- References

No definition available.

Name:	cznc_DepositsDisclosureAbstract
Namespace Prefix:	cznc_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Amount of time deposit liabilities, including certificates of deposit, in denominations that meet or exceed the Federal Deposit Insurance Corporation (FDIC) insurance limit.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-SubTopic 405
-Topic 942
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478353/942-405-50-1