Fair Value Measurements, By Balance Sheet Grouping (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Financial assets [Abstract]
Interest bearing time deposits with other banks	$ 10,528	$ 11,026
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	1,563,148	1,506,535
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	10,528	11,026
Loans held for sale	644	4,554
Net loans	1,470,482	1,426,698
Financial liabilities [Abstract]
Deposits	310,369	329,644
Borrowed funds	65,144	72,346
Carrying Amount [Member] \| Recurring [Member]
Financial assets [Abstract]
Interest bearing time deposits with other banks	10,528	11,026
Loans held for sale	644	4,554
Net loans	1,461,139	1,424,229
Financial liabilities [Abstract]
Deposits	1,879,090	1,836,151
Borrowed funds	68,214	73,977
Fair Value [Member] \| Recurring [Member]
Financial assets [Abstract]
Interest bearing time deposits with other banks	10,528	11,026
Loans held for sale	644	4,554
Net loans	1,470,482	1,426,698
Financial liabilities [Abstract]
Deposits	1,873,517	1,836,179
Borrowed funds	$ 65,144	$ 72,346

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 http://asc.fasb.org/extlink&oid=123466577&loc=SL123495737-112612

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=123594938&loc=d3e13433-108611

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
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-Section 50
-Paragraph 1D
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-URI http://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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- 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 http://asc.fasb.org/subtopic&trid=2196772

+ Details

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