Financial Instruments with Off-Balance-Sheet Risk - Additional Information (Details) $ in Millions	12 Months Ended
Dec. 31, 2022 USD ($)
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Collateralized letters of credit outstanding	$ 6.9
Excess of insurance limits held in cash accounts	$ 11.0

Excess Of Insurance Limits Held In Cash Accounts In Other Commercial Banks

No definition available.

Name:	efsi_ExcessOfInsuranceLimitsHeldInCashAccountsInOtherCommercialBanks
Namespace Prefix:	efsi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration