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Shareholders' Equity (Changes in Shares of Common Stock) (Details) - shares	3 Months Ended					9 Months Ended
	Jun. 30, 2022	Mar. 31, 2022	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2022
Shareholders Equity [Line Items]
Treasury stock, beginning balance		354,103				354,103
Shares issued, beginning balance	16,099,556	16,099,556	16,099,556	16,099,556	16,099,556	16,099,556
Treasury stock purchases						766,447
Treasury stock, ending balance						765,465
Shares issued, ending balance	16,099,556	16,099,556	16,099,556	16,099,556	16,099,556	16,099,556
Common Stock [Member]
Shareholders Equity [Line Items]
Shares outstanding, beginning balance	15,299,077	15,745,453	15,841,929	15,828,899	16,041,926	15,745,453
Shares issued for Landmark Group acquisition					12,831
Restricted stock units released	31,141	23,271			18,819
Restricted stock awards issued	11,300			9,350
Stock awards	3,848			3,680
Restricted stock awards released			250
Treasury stock purchases	(11,275)	(469,647)	(98)		(244,677)
Shares outstanding, ending balance	15,334,091	15,299,077	15,842,081	15,841,929	15,828,899	15,334,091
Treasury Stock [Member]
Shareholders Equity [Line Items]
Treasury stock, beginning balance	800,479	354,103	257,627	270,657	57,630	354,103
Shares issued for Landmark Group acquisition					(12,831)
Restricted stock units released	(31,141)	(23,271)			(18,819)
Restricted stock awards issued	(11,300)			(9,350)
Stock awards	(3,848)			(3,680)
Restricted stock awards released			(250)
Treasury stock purchases	11,275	469,647	98		244,677
Treasury stock, ending balance	765,465	800,479	257,475	257,627	270,657	765,465

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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 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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