Securities (Unrealized Losses On Available For Sale Securities) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
Investments In Debt And Marketable Equity Securities [Line Items]
Total temporarily impaired, Less than 12 months, Fair value	$ 7,228	$ 12,249
Total temporarily impaired, More than 12 months, Fair Value	13,971	19,791
Total temporarily impaired, Total, Fair value	21,199	32,040
Total temporarily impaired, Less than 12 months, Unrealized losses	(25)	(57)
Total temporarily impaired, More than 12 months, Unrealized losses	(261)	(544)
Total temporarily impaired, Total, Unrealized losses	(286)	(601)
US Government Agencies Debt Securities [Member]
Investments In Debt And Marketable Equity Securities [Line Items]
Available for Sale, Less than 12 months, Fair Value	1,991	3,906
Available for Sale, 12 months or longer, Fair Value	5,887	7,751
Available for Sale, Total, Fair Value	7,878	11,657
Available for sale, Less than 12 months, Unrealized losses	(9)	(26)
Available for sale, 12 months or more, Unrealized losses	(113)	(249)
Available for sale, Total, Unrealized losses	(122)	(275)
States and Political Subdivisions Debt Securities [Member]
Investments In Debt And Marketable Equity Securities [Line Items]
Available for Sale, Less than 12 months, Fair Value	1,989	4,752
Available for Sale, 12 months or longer, Fair Value	1,130	1,902
Available for Sale, Total, Fair Value	3,119	6,654
Available for sale, Less than 12 months, Unrealized losses	(10)	(9)
Available for sale, 12 months or more, Unrealized losses	(18)	(40)
Available for sale, Total, Unrealized losses	(28)	(49)
Held To Maturity, Less than 12 months, Fair Value	371	371
Held To Maturity, 12 months or longer, Fair Value	473	556
Held To Maturity, Total, Fair Value	844	927
Held to maturity, Less than 12 months, Unrealized losses	(1)	(1)
Held to maturity, 12 months or more, Unrealized losses	(24)	(31)
Held to maturity, Total, Unrealized losses	(25)	(32)
Debt Securities [Member]
Investments In Debt And Marketable Equity Securities [Line Items]
Available for Sale, Less than 12 months, Fair Value	3,980	8,658
Available for Sale, 12 months or longer, Fair Value	7,017	9,653
Available for Sale, Total, Fair Value	10,997	18,311
Available for sale, Less than 12 months, Unrealized losses	(19)	(35)
Available for sale, 12 months or more, Unrealized losses	(131)	(289)
Available for sale, Total, Unrealized losses	(150)	(324)
FNMA [Member]
Investments In Debt And Marketable Equity Securities [Line Items]
Available for Sale, Less than 12 months, Fair Value		1,498
Available for Sale, 12 months or longer, Fair Value		1,731
Available for Sale, Total, Fair Value		3,229
Available for sale, Less than 12 months, Unrealized losses		(10)
Available for sale, 12 months or more, Unrealized losses		(5)
Available for sale, Total, Unrealized losses		(15)
FHLMC [Member]
Investments In Debt And Marketable Equity Securities [Line Items]
Available for Sale, 12 months or longer, Fair Value	1,454	1,482
Available for Sale, Total, Fair Value	1,454	1,482
Available for sale, 12 months or more, Unrealized losses	(46)	(64)
Available for sale, Total, Unrealized losses	(46)	(64)
GNMA [Member]
Investments In Debt And Marketable Equity Securities [Line Items]
Available for Sale, Less than 12 months, Fair Value	1,207
Available for Sale, 12 months or longer, Fair Value	795	2,079
Available for Sale, Total, Fair Value	2,002	2,079
Available for sale, Less than 12 months, Unrealized losses	(1)
Available for sale, 12 months or more, Unrealized losses	(8)	(27)
Available for sale, Total, Unrealized losses	(9)	(27)
CMO [Member]
Investments In Debt And Marketable Equity Securities [Line Items]
Available for Sale, Less than 12 months, Fair Value	1,670	1,722
Available for Sale, 12 months or longer, Fair Value	4,232	4,290
Available for Sale, Total, Fair Value	5,902	6,012
Available for sale, Less than 12 months, Unrealized losses	(4)	(11)
Available for sale, 12 months or more, Unrealized losses	(52)	(128)
Available for sale, Total, Unrealized losses	(56)	(139)
Mortgage-backed Securities [Member]
Investments In Debt And Marketable Equity Securities [Line Items]
Available for Sale, Less than 12 months, Fair Value	2,877	3,220
Available for Sale, 12 months or longer, Fair Value	6,481	9,582
Available for Sale, Total, Fair Value	9,358	12,802
Available for sale, Less than 12 months, Unrealized losses	(5)	(21)
Available for sale, 12 months or more, Unrealized losses	(106)	(224)
Available for sale, Total, Unrealized losses	$ (111)	$ (245)

Available For Sale And Held To Maturity Securities Continuous Unrealized Loss Position Aggregate Losses

No definition available.

Name:	evbn_AvailableForSaleAndHeldToMaturitySecuritiesContinuousUnrealizedLossPositionAggregateLosses
Namespace Prefix:	evbn_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Available For Sale And Held To Maturity Securities Continuous Unrealized Loss Position Fair Value

+ References

No definition available.

+ Details

Name:	evbn_AvailableForSaleAndHeldToMaturitySecuritiesContinuousUnrealizedLossPositionFairValue
Namespace Prefix:	evbn_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Available For Sale And Held To Maturity Securities Continuous Unrealized Loss Position Less Than Twelve Months Aggregate Losses

+ References

No definition available.

+ Details

Name:	evbn_AvailableForSaleAndHeldToMaturitySecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsAggregateLosses
Namespace Prefix:	evbn_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Available For Sale And Held To Maturity Securities Continuous Unrealized Loss Position Less Than Twelve Months Fair Value

+ References

No definition available.

+ Details

Name:	evbn_AvailableForSaleAndHeldToMaturitySecuritiesContinuousUnrealizedLossPositionLessThanTwelveMonthsFairValue
Namespace Prefix:	evbn_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Available For Sale And Held To Maturity Securities Continuous Unrealized Loss Position More Than Twelve Months Aggregate Losses

+ References

No definition available.

+ Details

Name:	evbn_AvailableForSaleAndHeldToMaturitySecuritiesContinuousUnrealizedLossPositionMoreThanTwelveMonthsAggregateLosses
Namespace Prefix:	evbn_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Available For Sale And Held To Maturity Securities Continuous Unrealized Loss Position More Than Twelve Months Fair Value

+ References

No definition available.

+ Details

Name:	evbn_AvailableForSaleAndHeldToMaturitySecuritiesContinuousUnrealizedLossPositionMoreThanTwelveMonthsFairValue
Namespace Prefix:	evbn_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

Name:	evbn_InvestmentsInDebtAndMarketableEquitySecuritiesLineItems
Namespace Prefix:	evbn_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale that have been in a continuous loss position for twelve months or longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 7

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27337-111563

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 6

-Subparagraph (a)(2)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563

+ Details

Name:	us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale in a continuous loss position.

+ References

+ Details

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

- Definition

This item represents the aggregate fair value of investments in debt and equity securities in an unrealized loss position which are categorized neither as held-to-maturity nor trading securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 6

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563

+ Details

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

- Definition

Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale that have been in a continuous loss position for less than twelve months.

+ References

+ Details

Name:	us-gaap_AvailableForSaleSecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

This item represents the aggregate fair value of investments in debt and equity securities categorized neither as held-to-maturity nor trading securities that have been in a continuous unrealized loss position for less than twelve months.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 7

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27337-111563

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 6

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563

+ Details

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

- Definition

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 7

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27337-111563

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 6

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563

+ Details

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

- Definition

Amount of accumulated unrealized loss on investments in debt securities classified as held-to-maturity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 5

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27232-111563

+ Details

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

- Definition

Amount of accumulated unrealized loss on investments in debt securities classified as held-to-maturity that have been in a continuous loss position for twelve months or longer.

+ References

+ Details

Name:	us-gaap_HeldToMaturitySecuritiesContinuousUnrealizedLossPosition12MonthsOrLongerAccumulatedLoss
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

This item represents the fair value of securities categorized as held-to-maturity which are in an unrealized loss position.

+ References

+ Details

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

- Definition

Amount of accumulated unrealized loss on investments in debt securities classified as held-to-maturity that have been in a continuous loss position for less than twelve months.

+ References

+ Details

Name:	us-gaap_HeldToMaturitySecuritiesContinuousUnrealizedLossPositionLessThan12MonthsAccumulatedLoss
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

This item represents the fair value of securities categorized as held-to-maturity that have been in a continuous unrealized loss position for less than twelve months.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 7

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27337-111563

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 6

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563

+ Details

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

- Definition

This item represents the fair value of securities categorized as held-to-maturity securities that have been in a continuous unrealized loss position for twelve months or longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 7

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27337-111563

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 50

-Paragraph 6

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563

+ Details

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

- Details

Name:	us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_CollateralizedMortgageObligationsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_DebtSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_FederalHomeLoanMortgageCorporationCertificatesAndObligationsFHLMCMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_FederalNationalMortgageAssociationCertificatesAndObligationsFNMAMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_GovernmentNationalMortgageAssociationCertificatesAndObligationsGNMAMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_MortgageBackedSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_USGovernmentAgenciesDebtSecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis=us-gaap_USStatesAndPoliticalSubdivisionsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: