Shareholders' Equity (Changes in Shares of Common Stock) (Details) - shares	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Shareholders Equity [Line Items]
Treasury stock, beginning balance	96,657
Shares issued, beginning balance	16,099,556	16,056,178
Common stock issued for Courier Capital contingent earn-out		43,378
Restricted stock awards issued
Restricted stock units released
Stock awards
Treasury stock purchases
Treasury stock, ending balance	57,630	96,657
Shares issued, ending balance	16,099,556	16,099,556
Common Stock [Member]
Shareholders Equity [Line Items]
Shares outstanding, beginning balance	16,002,899	15,928,598
Common stock issued for Courier Capital contingent earn-out		43,378
Restricted stock awards issued	12,798	8,226
Restricted stock units released	24,921	28,080
Stock awards	8,439	4,192
Treasury stock purchases	(7,131)	(9,575)
Shares outstanding, ending balance	16,041,926	16,002,899
Treasury Stock [Member]
Shareholders Equity [Line Items]
Treasury stock, beginning balance	96,657	127,580
Common stock issued for Courier Capital contingent earn-out
Restricted stock awards issued	(12,798)	(8,226)
Restricted stock units released	(24,921)	(28,080)
Stock awards	(8,439)	(4,192)
Treasury stock purchases	7,131	9,575
Treasury stock, ending balance	57,630	96,657

Shareholders Equity [Line Items]

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Stock released during period shares restricted stock units.

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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 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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Number of shares that have been repurchased during the period and are being held in treasury.

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