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Shareholders' Equity (Changes In Shares Of Common Stock) (Details) - shares	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Shareholders Equity [Line Items]
Treasury stock, beginning balance	131,240
Shares issued, beginning balance	16,056,178	14,692,214
Common stock issued for "at-the-market" equity offering	1,363,964	1,363,964
Restricted stock awards issued
Restricted stock awards forfeited
Stock options exercised
Stock awards
Treasury stock purchases
Treasury stock, ending balance	127,580	131,240
Shares issued, ending balance	16,056,178	16,056,178
Common Stock [Member]
Shareholders Equity [Line Items]
Shares outstanding, beginning balance	15,924,938	14,537,597
Common stock issued for "at-the-market" equity offering		1,363,964
Restricted stock awards issued	7,370	8,898
Restricted stock awards forfeited	(23,901)	(10,359)
Stock options exercised	17,450	21,320
Stock awards	6,363	7,841
Treasury stock purchases	(3,622)	(4,323)
Shares outstanding, ending balance	15,928,598	15,924,938
Treasury Stock [Member]
Shareholders Equity [Line Items]
Treasury stock, beginning balance	131,240	154,617
Common stock issued for "at-the-market" equity offering
Restricted stock awards issued	(7,370)	(8,898)
Restricted stock awards forfeited	23,901	10,359
Stock options exercised	(17,450)	(21,320)
Stock awards	(6,363)	(7,841)
Treasury stock purchases	3,622	4,323
Treasury stock, ending balance	127,580	131,240

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

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Number of treasury shares (units) reissued during the period, excluding reissuance of shares (units) held in treasury used to satisfy equity-based compensation obligations exercised by the holders of such rights. Upon reissuance of shares (units) from treasury, either the common or preferred stock (unit) reissued is outstanding.

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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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