Shareholders' Equity (Changes In Shares Of Common Stock) (Details)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Shareholders Equity [Line Items]
Treasury stock, beginning balance	332,242us-gaap_TreasuryStockShares
Shares issued, beginning balance	14,161,597us-gaap_CommonStockSharesIssued
Stock options exercised	34,082
Treasury stock, ending balance	279,461us-gaap_TreasuryStockShares
Shares issued, ending balance	14,397,509us-gaap_CommonStockSharesIssued
Common Stock [Member]
Shareholders Equity [Line Items]
Shares outstanding, beginning balance	13,829,355	13,787,709
Shares issued for the SDN acquisition	235,912
Restricted stock awards issued	43,242
Restricted stock awards forfeited	(15,441)
Restricted stock awards issued, net of forfeitures		24,058
Stock options exercised	34,082	23,265
Treasury stock purchases	(9,102)	(11,349)
Directors' retainer		5,672
Shares outstanding, ending balance	14,118,048	13,829,355
Treasury Stock [Member]
Shareholders Equity [Line Items]
Treasury stock, beginning balance	332,242	373,888
Restricted stock awards issued	(43,242)
Restricted stock awards forfeited	15,441
Restricted stock awards issued, net of forfeitures		(24,058)
Stock options exercised	(34,082)	(23,265)
Treasury stock purchases	9,102	11,349
Directors' retainer		(5,672)
Treasury stock, ending balance	279,461	332,242
Common Stock Issued [Member]
Shareholders Equity [Line Items]
Shares issued, beginning balance	14,161,597		14,161,597
Shares issued for the SDN acquisition	235,912
Shares issued, ending balance	14,397,509		14,161,597

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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Number of shares of stock issued during the period pursuant to acquisitions.

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Number of shares related to Restricted Stock Award forfeited during the period.

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Total number of shares issued during the period, including shares forfeited, as a result of Restricted Stock Awards.

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Number of shares issued during the period related to Restricted Stock Awards, net of any shares forfeited.

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Number of share options (or share units) exercised during the current period.

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Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

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