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Shareholders' Equity (Changes in Shares of Common Stock) (Details) - shares	3 Months Ended
	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019
Shareholders Equity [Line Items]
Shares outstanding, beginning balance			16,099,556
Treasury stock, beginning balance		96,657
Shares issued, beginning balance	16,099,556	16,099,556		16,056,178	16,056,178
Common stock issued for Courier Capital contingent earn-out				43,378
Shares outstanding, ending balance	16,099,556		16,099,556	16,099,556
Shares issued, ending balance		16,099,556			16,056,178
Common Stock [Member]
Shareholders Equity [Line Items]
Shares outstanding, beginning balance	16,019,384	16,002,899	15,994,697	15,940,810	15,928,598
Restricted stock units released		22,921	2,500		18,580
Common stock issued for Courier Capital contingent earn-out				43,378
Restricted stock awards issued	12,798			8,226
Stock awards	5,403			2,283
Treasury stock purchases		(6,436)	(839)		(6,368)
Shares outstanding, ending balance	16,037,585	16,019,384	15,996,358	15,994,697	15,940,810
Treasury Stock [Member]
Shareholders Equity [Line Items]
Treasury stock, beginning balance	80,172	96,657	104,859	115,368	127,580
Restricted stock units released		(22,921)	(2,500)		(18,580)
Restricted stock awards issued	(12,798)			(8,226)
Stock awards	(5,403)			(2,283)
Treasury stock purchases		6,436	839		6,368
Treasury stock, ending balance	61,971	80,172	103,198	104,859	115,368

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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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