REGULATORY MATTERS (Details) $ in Thousands	12 Months Ended
Dec. 31, 2016 USD ($) Category	Dec. 31, 2015 USD ($)
Dividend Restrictions [Abstract]
Number of preceding years retained net income used for restrictions on dividend declaration	2 years
Dividends that can be declared without the approval of the Comptroller of the Currency	$ 13,925
Loans [Abstract]
Regulatory lending limit	$ 17,631
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Number of capital categories \| Category	5
Bank [Member]
Actual Amount [Abstract]
Total capital (to risk-weighted assets)	$ 117,537	$ 108,232
Tier 1 capital (to risk-weighted assets)	108,419	100,958
Common equity tier 1 capital (to risk weighted assets)	108,419	100,958
Tier 1 capital (to average assets)	$ 108,419	$ 100,958
Actual Ratio [Abstract]
Total capital (to risk-weighted assets)	14.46%	15.34%
Tier 1 capital (to risk-weighted assets)	13.34%	14.31%
Common equity Tier 1 capital (to risk weighted assets)	13.34%	14.31%
Tier 1 capital (to average assets)	9.13%	10.35%
For Capital Adequacy Purposes Amount [Abstract]
Total capital (to risk-weighted assets)	$ 65,020	$ 56,443
Tier 1 capital (to risk-weighted assets)	48,765	42,332
Common equity Tier 1 capital (to risk weighted assets)	36,574	31,749
Tier 1 capital (to average assets)	$ 39,006	$ 39,006
For Capital Adequacy Purposes Ratio [Abstract]
Total capital (to risk-weighted assets)	8.00%	8.00%
Tier 1 capital (to risk-weighted assets)	6.00%	6.00%
Common equity Tier 1 capital (to risk weighted assets)	4.50%	4.50%
Tier 1 capital (to average assets)	4.00%	4.00%
To Be Well Capitalized Under Prompt Corrective Action Provisions Amount [Abstract]
Total capital (to risk-weighted assets)	$ 81,275	$ 70,554
Tier 1 capital (to risk-weighted assets)	65,020	56,443
Common equity Tier 1 capital (to risk weighted assets)	52,829	45,860
Tier 1 capital (to average assets)	$ 48,757	$ 48,757
To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio [Abstract]
Total capital (to risk-weighted assets)	10.00%	10.00%
Tier 1 capital (to risk-weighted assets)	8.00%	8.00%
Common equity Tier 1 capital (to risk weighted assets)	6.50%	6.50%
Tier 1 capital (to average assets)	5.00%	5.00%
Company [Member]
Actual Amount [Abstract]
Total capital (to risk-weighted assets)	$ 121,717	$ 114,886
Tier 1 capital (to risk-weighted assets)	112,599	107,612
Common equity tier 1 capital (to risk weighted assets)	105,099	100,112
Tier 1 capital (to average assets)	$ 112,599	$ 107,612
Actual Ratio [Abstract]
Total capital (to risk-weighted assets)	14.93%	16.23%
Tier 1 capital (to risk-weighted assets)	13.81%	15.20%
Common equity Tier 1 capital (to risk weighted assets)	12.89%	14.14%
Tier 1 capital (to average assets)	9.46%	11.01%
For Capital Adequacy Purposes Amount [Abstract]
Total capital (to risk-weighted assets)	$ 65,217	$ 56,630
Tier 1 capital (to risk-weighted assets)	48,913	42,472
Common equity Tier 1 capital (to risk weighted assets)	36,685	31,854
Tier 1 capital (to average assets)	$ 47,586	$ 39,083
For Capital Adequacy Purposes Ratio [Abstract]
Total capital (to risk-weighted assets)	8.00%	8.00%
Tier 1 capital (to risk-weighted assets)	6.00%	6.00%
Common equity Tier 1 capital (to risk weighted assets)	4.50%	4.50%
Tier 1 capital (to average assets)	4.00%	4.00%
To Be Well Capitalized Under Prompt Corrective Action Provisions Amount [Abstract]
Total capital (to risk-weighted assets)	$ 81,522	$ 70,787
Tier 1 capital (to risk-weighted assets)	65,217	56,630
Common equity Tier 1 capital (to risk weighted assets)	52,989	46,012
Tier 1 capital (to average assets)	$ 59,483	$ 48,854
To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio [Abstract]
Total capital (to risk-weighted assets)	10.00%	10.00%
Tier 1 capital (to risk-weighted assets)	8.00%	8.00%
Common equity Tier 1 capital (to risk weighted assets)	6.50%	6.50%
Tier 1 capital (to average assets)	5.00%	5.00%

No definition available.

Name:	czfs_ActualAmountAbstract
Namespace Prefix:	czfs_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- References

No definition available.

+ Details

Name:	czfs_DividendRestrictionsAbstract
Namespace Prefix:	czfs_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- References

No definition available.

+ Details

Name:	czfs_ForCapitalAdequacyPurposesAbstract
Namespace Prefix:	czfs_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- References

No definition available.

+ Details

Name:	czfs_ForCapitalAdequacyPurposesRatioAbstract
Namespace Prefix:	czfs_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- References

No definition available.

+ Details

Name:	czfs_LoansAbstract
Namespace Prefix:	czfs_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of capital categories during the period.

+ References

No definition available.

+ Details

Name:	czfs_NumberOfCapitalCategories
Namespace Prefix:	czfs_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

The number of preceding years retained net income used for determining the restrictions on dividend declarations.

+ References

No definition available.

+ Details

Name:	czfs_NumberOfPrecedingYearsRetainedNetIncomeUsedForRestrictionsOnDividendDeclaration
Namespace Prefix:	czfs_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Lending limit due to regulatory regulations.

+ References

No definition available.

+ Details

Name:	czfs_RegulatoryLendingLimit
Namespace Prefix:	czfs_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Common equity Tier 1 Risk Based equity as defined in the regulations.

+ References

No definition available.

+ Details

Name:	czfs_TierOneRiskBasedCommonEquity
Namespace Prefix:	czfs_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Common equity Tier 1 Risk Based equity required for capital adequacy as defined in the regulations.

+ References

No definition available.

+ Details

Name:	czfs_TierOneRiskBasedCommonEquityRequiredForCapitalAdequacy
Namespace Prefix:	czfs_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Refers to Tier 1 common equity divided by risk weighted assets required for capital adequacy purposes as defined by regulations.

+ References

No definition available.

+ Details

Name:	czfs_TierOneRiskBasedCommonEquityRequiredForCapitalAdequacyToRiskWeightedAssets
Namespace Prefix:	czfs_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Common equity Tier 1 Risk Based equity required to be categorized as well capitalized as defined in the regulations.

+ References

No definition available.

+ Details

Name:	czfs_TierOneRiskBasedCommonEquityRequiredToBeWellCapitalized
Namespace Prefix:	czfs_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Refers to Tier 1 common equity divided by risk weighted assets required to be categorized as well capitalized as defined by regulations.

+ References

No definition available.

+ Details

Name:	czfs_TierOneRiskBasedCommonEquityRequiredToBeWellCapitalizedToRiskWeightedAssets
Namespace Prefix:	czfs_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Refers to Tier 1 common equity divided by risk weighted assets as defined by regulations.

+ References

No definition available.

+ Details

Name:	czfs_TierOneRiskBasedCommonEquityToRiskWeightedAssets
Namespace Prefix:	czfs_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- References

No definition available.

+ Details

Name:	czfs_ToBeWellCapitalizedUnderPromptCorrectiveActionProvisionsAmountAbstract
Namespace Prefix:	czfs_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- References

No definition available.

+ Details

Name:	czfs_ToBeWellCapitalizedUnderPromptCorrectiveActionProvisionsRatioAbstract
Namespace Prefix:	czfs_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The amount of total capital as defined in the regulations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 948
-SubTopic 10
-Section 50
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=6490092&loc=d3e47304-110998

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1H
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=35709795&loc=d3e65071-112826

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1H
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=35709795&loc=d3e65071-112826

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 948
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=6490092&loc=d3e47080-110998

+ Details

Name:	us-gaap_Capital
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The minimum amount of Total Capital required for capital adequacy purposes under the regulatory framework for prompt corrective action.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1H
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=35709795&loc=d3e65071-112826

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=35709795&loc=SL5958568-112826

+ Details

Name:	us-gaap_CapitalRequiredForCapitalAdequacy
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The minimum Total risk based capital ratio (total capital divided by risk weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=35709795&loc=SL5958568-112826

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1H
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=35709795&loc=d3e65071-112826

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=35709795&loc=SL5958570-112826

+ Details

Name:	us-gaap_CapitalRequiredForCapitalAdequacyToRiskWeightedAssets
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The amount of Total Capital required to be categorized as well as capitalized under the regulatory framework for prompt corrective action.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=35709795&loc=SL5958568-112826

+ Details

Name:	us-gaap_CapitalRequiredToBeWellCapitalized
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The Total risk based capital ratio (total capital divided by risk weighted assets) required to be categorized as "well capitalized", in the regulatory framework for prompt corrective action.

+ References

+ Details

Name:	us-gaap_CapitalRequiredToBeWellCapitalizedToRiskWeightedAssets
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Total Capital divided by risk weighted assets as defined in the regulations.

+ References

+ Details

Name:	us-gaap_CapitalToRiskWeightedAssets
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- 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

Name:	us-gaap_ComplianceWithRegulatoryCapitalRequirementsUnderBankingRegulationsLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- References

No definition available.

+ Details

Name:	us-gaap_RiskBasedRatiosAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of dividends that can be declared or paid without approval of regulatory agency.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(e))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

Name:	us-gaap_StatutoryAccountingPracticesStatutoryAmountAvailableForDividendPaymentsWithoutRegulatoryApproval
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Tier 1 Leverage Capital as defined in the regulations. Also called Core Capital.

+ References

+ Details

Name:	us-gaap_TierOneLeverageCapital
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The minimum amount of Tier 1 Leverage Capital required for capital adequacy purposes under the regulatory framework for prompt corrective action.

+ References

+ Details

Name:	us-gaap_TierOneLeverageCapitalRequiredForCapitalAdequacy
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The minimum amount of Tier 1 Leverage Capital for capital adequacy purposes divided by average assets as defined in the regulations.

+ References

+ Details

Name:	us-gaap_TierOneLeverageCapitalRequiredForCapitalAdequacyToAverageAssets
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The amount of Tier 1 Leverage Capital required to be categorized as well capitalized under the regulatory framework for prompt corrective action.

+ References

+ Details

Name:	us-gaap_TierOneLeverageCapitalRequiredToBeWellCapitalized
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The amount of Tier 1 Leverage Capital required to be categorized as well capitalized divided by average assets as defined in the regulatory framework for prompt corrective action.

+ References

+ Details

Name:	us-gaap_TierOneLeverageCapitalRequiredToBeWellCapitalizedToAverageAssets
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Tier 1 Leverage Capital divided by average assets as defined in the regulations.

+ References

+ Details

Name:	us-gaap_TierOneLeverageCapitalToAverageAssets
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Tier 1 Risk Based Capital as defined in the regulations.

+ References

+ Details

Name:	us-gaap_TierOneRiskBasedCapital
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The minimum amount of Tier 1 Risk Based Capital required for capital adequacy purposes under the regulatory framework for prompt corrective action.

+ References

+ Details

Name:	us-gaap_TierOneRiskBasedCapitalRequiredForCapitalAdequacy
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The minimum Tier One Capital Ratio (Tier one capital divided by risk-weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=35709795&loc=SL5958568-112826

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=35709795&loc=SL5958570-112826

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 505
-Section 50
-Paragraph 1H
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=35709795&loc=d3e65071-112826

+ Details

Name:	us-gaap_TierOneRiskBasedCapitalRequiredForCapitalAdequacyToRiskWeightedAssets
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The amount of Tier 1 Risk Based Capital required to be categorized as well capitalized under the regulatory framework for prompt corrective action.

+ References

+ Details

Name:	us-gaap_TierOneRiskBasedCapitalRequiredToBeWellCapitalized
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The Tier 1 capital ratio (Tier 1 capital divided by risk weighted assets) required to be categorized as "well capitalized" under the regulatory framework for prompt corrective action.

+ References

+ Details

Name:	us-gaap_TierOneRiskBasedCapitalRequiredToBeWellCapitalizedToRiskWeightedAssets
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Tier 1 capital divided by risk weighted assets as defined by regulations.

+ References

+ Details

Name:	us-gaap_TierOneRiskBasedCapitalToRiskWeightedAssets
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Details

Name:	dei_LegalEntityAxis=us-gaap_SubsidiariesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	dei_LegalEntityAxis=us-gaap_ParentCompanyMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: