Condensed Financial Information - Parent Company Only (Schedule of Condensed Balance Sheets) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Assets
Due from banks	$ 9,075us-gaap_CashAndDueFromBanks	$ 9,295us-gaap_CashAndDueFromBanks
Securities available for sale	94,165us-gaap_AvailableForSaleSecurities	102,598us-gaap_AvailableForSaleSecurities
Other assets	9,436us-gaap_OtherAssets	9,766us-gaap_OtherAssets
Total assets	626,830us-gaap_Assets	586,444us-gaap_Assets
Liabilities and Shareholders’ Equity
Trust preferred capital notes	7,217efsi_PreferredCapitalNotesOfTrust	7,217efsi_PreferredCapitalNotesOfTrust
Other Liabilities	2,665us-gaap_OtherLiabilities	2,984us-gaap_OtherLiabilities
Total liabilities	553,698us-gaap_Liabilities	520,038us-gaap_Liabilities
Stockholders' Equity Attributable to Parent [Abstract]
Preferred stock	0us-gaap_PreferredStockValue	0us-gaap_PreferredStockValue
Common stock issued	8,621us-gaap_CommonStockValue	8,482us-gaap_CommonStockValue
Additional Paid in Capital	12,618us-gaap_AdditionalPaidInCapital	11,537us-gaap_AdditionalPaidInCapital
Retained earnings	50,578	46,082
Accumulated other comprehensive income	1,315	305	3,448	2,931
Total shareholders’ equity	73,132us-gaap_StockholdersEquity	66,406us-gaap_StockholdersEquity	63,706us-gaap_StockholdersEquity	58,090us-gaap_StockholdersEquity
Total liabilities and shareholders’ equity	626,830	586,444
Parent Company [Member]
Assets
Cash held in subsidiary bank	1,694	419
Due from banks	504	504
Securities available for sale	1,383	2,893
Investment in subsidiaries, at cost, plus undistributed net income	76,423	69,692
Other assets	661	575
Total assets	80,665	74,083
Liabilities and Shareholders’ Equity
Trust preferred capital notes	7,217	7,217
Other Liabilities	316	460
Total liabilities	7,533	7,677
Stockholders' Equity Attributable to Parent [Abstract]
Common stock issued	8,621	8,482
Additional Paid in Capital	12,618	11,537
Retained earnings	50,578	46,082
Accumulated other comprehensive income	1,315	305
Total shareholders’ equity	73,132	66,406
Total liabilities and shareholders’ equity	$ 80,665	$ 74,083

Cash Held In Subsidiary Bank

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Investment In Subsidiaries At Cost Plus Undistributed Net Income

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Preferred Capital Notes Of Trust

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Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

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Excess of issue price over par or stated value of the entity's capital stock and amounts received from other transactions involving the entity's stock or stockholders. Includes adjustments to additional paid in capital. Some examples of such adjustments include recording the issuance of debt with a beneficial conversion feature and certain tax consequences of equity instruments awarded to employees. Use this element for the aggregate amount of additional paid-in capital associated with common and preferred stock. For additional paid-in capital associated with only common stock, use the element additional paid in capital, common stock. For additional paid-in capital associated with only preferred stock, use the element additional paid in capital, preferred stock.

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Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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For banks and other depository institutions: Includes cash on hand (currency and coin), cash items in process of collection, noninterest bearing deposits due from other financial institutions (including corporate credit unions), and noninterest bearing balances with the Federal Reserve Banks, Federal Home Loan Banks and central banks.

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Aggregate par or stated value of issued nonredeemable common stock (or common stock redeemable solely at the option of the issuer). This item includes treasury stock repurchased by the entity. Note: elements for number of nonredeemable common shares, par value and other disclosure concepts are in another section within stockholders' equity.

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Sum of the carrying amounts as of the balance sheet date of all liabilities that are recognized. Liabilities are probable future sacrifices of economic benefits arising from present obligations of an entity to transfer assets or provide services to other entities in the future.

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Amount of liabilities and equity items, including the portion of equity attributable to noncontrolling interests, if any.

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The aggregate carrying amounts, as of the balance sheet date, of assets not separately disclosed in the balance sheet.

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The aggregate carrying amount, as of the balance sheet date, of liabilities not separately disclosed in the balance sheet.

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Aggregate par or stated value of issued nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer). This item includes treasury stock repurchased by the entity. Note: elements for number of nonredeemable preferred shares, par value and other disclosure concepts are in another section within stockholders' equity.

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The cumulative amount of the reporting entity's undistributed earnings or deficit.

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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