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Shareholders' Equity (Changes In Shares Of Common Stock) (Details) - shares	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Shareholders Equity [Line Items]
Treasury stock, beginning balance	127,580
Shares issued, beginning balance	16,056,178	16,056,178
Common stock issued for Courier Capital contingent earn-out	43,378
Restricted stock awards issued
Restricted stock awards forfeited
Stock options exercised
Stock awards
Treasury stock purchases
Treasury stock, ending balance	96,657	127,580
Shares issued, ending balance	16,099,556	16,056,178
Common Stock [Member]
Shareholders Equity [Line Items]
Shares outstanding, beginning balance	15,928,598	15,924,938
Common stock issued for Courier Capital contingent earn-out	43,378
Restricted stock awards issued	8,226	7,370
Restricted stock awards forfeited		(23,901)
Stock options exercised	28,080	17,450
Stock awards	4,192	6,363
Treasury stock purchases	(9,575)	(3,622)
Shares outstanding, ending balance	16,002,899	15,928,598
Treasury Stock [Member]
Shareholders Equity [Line Items]
Treasury stock, beginning balance	127,580	131,240
Common stock issued for Courier Capital contingent earn-out
Restricted stock awards issued	(8,226)	(7,370)
Restricted stock awards forfeited		23,901
Stock options exercised	(28,080)	(17,450)
Stock awards	(4,192)	(6,363)
Treasury stock purchases	9,575	3,622
Treasury stock, ending balance	96,657	127,580

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Shareholders Equity [Line Items]

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

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

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Number of treasury shares or units reissued. Excludes reissuance of shares or units in treasury for award under share-based payment arrangement.

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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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