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Shareholders' Equity (Changes in Shares of Common Stock) (Details) - shares	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Shareholders Equity [Line Items]
Treasury stock, beginning balance	96,657
Shares issued, beginning balance	16,099,556	16,056,178
Restricted stock units released
Restricted stock awards issued
Treasury stock purchases
Treasury stock, ending balance	80,172
Shares issued, ending balance	16,099,556	16,056,178
Common Stock [Member]
Shareholders Equity [Line Items]
Shares outstanding, beginning balance	16,002,899	15,928,598
Restricted stock units released	22,921	18,580
Treasury stock purchases	(6,436)	(6,368)
Shares outstanding, ending balance	16,019,384	15,940,810
Treasury Stock [Member]
Shareholders Equity [Line Items]
Treasury stock, beginning balance	96,657	127,580
Restricted stock units released	(22,921)	(18,580)
Treasury stock purchases	6,436	6,368
Treasury stock, ending balance	80,172	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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Total number of shares issued during the period, including shares forfeited, as a result of Restricted Stock Awards.

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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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