Fair Value Measurements, By Balance Sheet Grouping (Details) - USD ($) $ in Thousands	Mar. 31, 2023	Dec. 31, 2022
Financial assets [Abstract]
Interest bearing time deposits with other banks	$ 6,055	$ 6,055
Level I [Member] \| Recurring [Member]
Financial assets [Abstract]
Interest bearing time deposits with other banks	0	0
Loans held for sale	0	0
Net loans	0	0
Financial liabilities [Abstract]
Deposits	1,518,045	1,566,517
Borrowed funds	0	0
Level II [Member] \| Recurring [Member]
Financial assets [Abstract]
Interest bearing time deposits with other banks	0	0
Loans held for sale	0	0
Net loans	0	0
Financial liabilities [Abstract]
Deposits	0	0
Borrowed funds	0	0
Level III [Member] \| Recurring [Member]
Financial assets [Abstract]
Interest bearing time deposits with other banks	5,848	6,055
Loans held for sale	675	725
Net loans	1,644,211	1,662,514
Financial liabilities [Abstract]
Deposits	271,075	265,520
Borrowed funds	276,451	246,288
Carrying Amount [Member] \| Recurring [Member]
Financial assets [Abstract]
Interest bearing time deposits with other banks	6,055	6,055
Loans held for sale	671	725
Net loans	1,708,225	1,706,447
Financial liabilities [Abstract]
Deposits	1,799,687	1,844,208
Borrowed funds	288,059	257,278
Fair Value [Member] \| Recurring [Member]
Financial assets [Abstract]
Interest bearing time deposits with other banks	5,848	6,055
Loans held for sale	675	725
Net loans	1,644,211	1,662,514
Financial liabilities [Abstract]
Deposits	1,789,120	1,832,037
Borrowed funds	$ 276,451	$ 246,288

Interest bearing time deposits with other banks as of the balance sheet date.

No definition available.

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Namespace Prefix:	czfs_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Fair value portion of debt instrument payable, including, but not limited to, notes payable and loans payable.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 55
-Paragraph 69C
-URI https://asc.fasb.org/extlink&oid=123466577&loc=SL123495737-112612

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 55
-Paragraph 69B
-URI https://asc.fasb.org/extlink&oid=123466577&loc=SL123495735-112612

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-URI https://asc.fasb.org/extlink&oid=123594938&loc=d3e13433-108611

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 20
-Section 50
-Paragraph 1D
-Subparagraph (c)
-URI https://asc.fasb.org/extlink&oid=123466505&loc=SL123495340-112611

+ Details

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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.

+ Details

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Balance Type:	credit
Period Type:	instant

- References

No definition available.

+ Details

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Period Type:	duration

- References

No definition available.

+ Details

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

- 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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-URI https://asc.fasb.org/subtopic&trid=2196772

+ Details

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