Shareholders Equity [Line Items]

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- Definition

Stock released during period shares restricted stock units.

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- Definition

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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- Definition

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

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- Definition

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

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- Definition

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

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- Definition

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

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- Definition

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

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- Definition

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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Shareholders' Equity (Changes In Shares Of Common Stock) (Details) - shares	3 Months Ended
	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018
Shareholders Equity [Line Items]
Treasury stock, beginning balance			127,580
Shares issued, beginning balance	16,099,556	16,056,178	16,056,178	16,056,178	16,056,178	16,056,178
Restricted stock units released
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	103,198
Shares issued, ending balance	16,099,556	16,099,556	16,056,178	16,056,178	16,056,178	16,056,178
Common Stock [Member]
Shareholders Equity [Line Items]
Shares, beginning balance	15,994,697	15,940,810	15,928,598	15,924,159	15,901,415	15,924,938
Restricted stock units released	2,500		18,580
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				800	12,650	4,000
Stock awards		2,283			2,724
Treasury stock purchases	(839)		(6,368)			(3,622)
Shares, ending balance	15,996,358	15,994,697	15,940,810	15,924,959	15,924,159	15,901,415
Treasury Stock [Member]
Shareholders Equity [Line Items]
Treasury stock, beginning balance	104,859	115,368	127,580	132,019	154,763	131,240
Restricted stock units released	(2,500)		(18,580)
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				(800)	(12,650)	(4,000)
Stock awards		(2,283)			(2,724)
Treasury stock purchases	839		6,368			3,622
Treasury stock, ending balance	103,198	104,859	115,368	131,219	132,019	154,763