Restructurings for Borrowers Experiencing Financial Difficulty (Narrative) (Details) $ in Thousands	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022 USD ($) Loan Contract
Financing Receivable Modifications [Line Items]
Number of troubled debt restructured loans \| Loan		28
Mortgage Loans on Real Estate Weighted Average Term	1 year
Total troubled debt restructured loans \| $		$ 4,600
Financing Receivable, Modifications, Nonaccrual, Number of Contracts \| Loan		2
Financing Receivable, Modifications, Nonaccrual, Recorded Investment \| $		$ 133
Number of contractions modified by granting concession		13
Troubled debt restructuring modifications by granting a refinance		1
Troubled Debt Restructuring Modifications Number Of Contracts		13
Consumer Installment
Financing Receivable Modifications [Line Items]
Troubled Debt Restructuring Modifications Number Of Contracts		1
Residential Single Family
Financing Receivable Modifications [Line Items]
Troubled Debt Restructuring Modifications Number Of Contracts		9
Loan is considered payment default		30 days
Commercial Real Estate Owner Occupied [Member]
Financing Receivable Modifications [Line Items]
Troubled Debt Restructuring Modifications Number Of Contracts		1
Non Owner Occupied Commercial [Member]
Financing Receivable Modifications [Line Items]
Troubled Debt Restructuring Modifications Number Of Contracts		1
Construction And Farmland Residential Financing Receivable [Member]
Financing Receivable Modifications [Line Items]
Troubled Debt Restructuring Modifications Number Of Contracts		1
Residential Single Family Financing Receivable [Member]
Financing Receivable Modifications [Line Items]
Troubled Debt Restructuring Modifications Number Of Contracts		9

Number of financing receiviable modified loans that are in nonaccrual

No definition available.

Name:	efsi_FinancingReceivableModificationsNonaccrualNumberofContracts
Namespace Prefix:	efsi_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Financing Receivable, Modifications, Nonaccrual, Recorded Investment

+ References

No definition available.

+ Details

Name:	efsi_FinancingReceivableModificationsNonaccrualRecordedInvestment
Namespace Prefix:	efsi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Mortgage loans on real estate weighted average term

+ References

No definition available.

+ Details

Name:	efsi_MortgageLoansOnRealEstateWeightedAverageTerm
Namespace Prefix:	efsi_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Period Past Due Loan Considered Payment Default

+ References

No definition available.

+ Details

Name:	efsi_PeriodPastDueLoanConsideredPaymentDefault
Namespace Prefix:	efsi_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Troubled Debt Restructuring Modifications By Granting A Refinance.

+ References

No definition available.

+ Details

Name:	efsi_TroubledDebtRestructuringModificationsByGrantingARefinance
Namespace Prefix:	efsi_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Troubled debt restructuring modifications by granting a concession number of contracts.

+ References

No definition available.

+ Details

Name:	efsi_TroubledDebtRestructuringModificationsByGrantingConcessionNumberOfContracts
Namespace Prefix:	efsi_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Troubled debt restructuring modifications number of contracts.

+ References

No definition available.

+ Details

Name:	efsi_TroubledDebtRestructuringModificationsNumberOfContracts
Namespace Prefix:	efsi_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- 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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-42

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
-Subparagraph (a)(2)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-42

Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 12A
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481933/310-10-55-12A

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 33
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-33

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 34
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-34

+ Details

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

- Definition

Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 33
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-33

+ Details

Name:	us-gaap_FinancingReceivableModificationsNumberOfContracts2
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Accumulated amortized cost of financing receivable modified for debtor experiencing financial difficulty.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 42
-Subparagraph (a)(1)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-42

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 310
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 33
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481962/310-10-50-33

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 310
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481746/310-40-50-4

+ Details

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

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=efsi_ConsumerInstallmentFinancingReceivableMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=efsi_ResidentialSingleFamilyMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=efsi_CommercialRealEstateOwnerOccupiedMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=efsi_NonOwnerOccupiedCommercialMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=efsi_ConstructionAndFarmlandResidentialFinancingReceivableMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=efsi_ResidentialSingleFamilyFinancingReceivableMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: