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.

No definition available.

+ 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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=118936363&loc=SL6953676-111524

+ Details

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

- Definition

Amount, after troubled debt restructuring, of modified financing receivable.

+ References

+ Details

Name:	us-gaap_FinancingReceivableModificationsPostModificationRecordedInvestment2
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount, before troubled debt restructuring, of financing receivable to be modified.

+ References

+ Details

Name:	us-gaap_FinancingReceivableModificationsPreModificationRecordedInvestment2
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_CommercialPortfolioSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LoanRestructuringModificationAxis=us-gaap_ExtendedMaturityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LoanRestructuringModificationAxis=evbn_TermOutLineOfCreditMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_ResidentialPortfolioSegmentMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_EquitySecuritiesByIndustryAxis=us-gaap_RealEstateSectorMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LoanRestructuringModificationAxis=evbn_ExtendedMaturityAndContractualInterestRateReductionMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_LoanRestructuringModificationAxis=evbn_CombinationOfConcessionsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_HomeEquityMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Loans And The Allowance For Loan Losses (TDR Activity By Type Of Concession Granted To Borrower) (Details) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020 USD ($) contract	Sep. 30, 2019 USD ($) contract	Sep. 30, 2020 USD ($) contract	Sep. 30, 2019 USD ($) contract
Commercial And Industrial [Member] \| Extension Of Maturity [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract		1		1
Pre-Modification Outstanding Recorded Investment		$ 21		$ 21
Post-Modification Outstanding Recorded Investment		$ 21		$ 21
Commercial And Industrial [Member] \| Term-Out Line Of Credit [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract		1		1
Pre-Modification Outstanding Recorded Investment		$ 42		$ 42
Post-Modification Outstanding Recorded Investment		$ 42		$ 42
Residential Mortgages [Member] \| Total Real Estate Loans [Member] \| Extension Of Maturity And Interest Rate Reduction [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract	1	3	1	3
Pre-Modification Outstanding Recorded Investment	$ 97	$ 307	$ 97	$ 307
Post-Modification Outstanding Recorded Investment	$ 97	$ 307	$ 97	$ 307
Residential Mortgages [Member] \| Total Real Estate Loans [Member] \| Combination Of Concessions [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract			1
Pre-Modification Outstanding Recorded Investment			$ 56
Post-Modification Outstanding Recorded Investment			$ 56
Home Equity Loans [Member] \| Total Real Estate Loans [Member] \| Extension Of Maturity And Interest Rate Reduction [Member]
Financing Receivable, Modifications [Line Items]
Number of Contracts \| contract		1		3
Pre-Modification Outstanding Recorded Investment		$ 110		$ 390
Post-Modification Outstanding Recorded Investment		$ 110		$ 390