Consolidated Statements of Changes In Stockholders' Equity - USD ($) $ in Thousands		Total	Common Stock	Additional Paid-In Capital	Retained Earnings	Accumulated Other Comprehensive Loss	Treasury Stock
Stockholders' equity, beginning balance at Dec. 31, 2021		$ 371,186	$ 20,800	$ 377,996	$ 54,078	$ 347	$ (82,035)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income		36,712			36,712
Other Comprehensive Income (Loss)		(49,417)				(49,417)
Stock Dividend		0	624	19,408	(20,032)
Cash Dividends Paid	[1]	(12,980)			(12,980)
Stock Options Exercised, Net		366		215			151
Shares Issued Under the Directors' Stock Plan		285		210			75
Shares Issued Under the Employee Stock Purchase Plan		361		261			100
Shares Issued for Dividend Reinvestment Plans		1,420		1,033			387
Stock-Based Compensation Expense		338		338
Purchases of Treasury Stock		(2,721)					(2,721)
Stockholders' equity, ending balance at Sep. 30, 2022		345,550	21,424	399,461	57,778	(49,070)	(84,043)
Stockholders' equity, beginning balance at Jun. 30, 2022		356,498	20,800	379,423	69,980	(29,564)	(84,141)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income		12,163
Other Comprehensive Income (Loss)		(19,506)				(19,506)
Stock Dividend		0	624	19,408	(20,032)
Cash Dividends Paid	[1]	(4,333)			(4,333)
Stock Options Exercised, Net		40		27			13
Shares Issued Under the Directors' Stock Plan		92		67			25
Shares Issued Under the Employee Stock Purchase Plan		119		85			34
Shares Issued for Dividend Reinvestment Plans		471		337			134
Stock-Based Compensation Expense		114		114
Purchases of Treasury Stock		(108)					(108)
Stockholders' equity, ending balance at Sep. 30, 2022		345,550	21,424	399,461	57,778	(49,070)	(84,043)
Stockholders' equity, beginning balance at Dec. 31, 2022		353,538	21,424	400,270	65,401	(49,655)	(83,902)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income		22,352			22,352
Other Comprehensive Income (Loss)		(2,929)				(2,929)
Stock Dividend		0	643	11,058	(11,701)
Cash Dividends Paid	[1]	(13,405)			(13,405)
Stock Options Exercised, Net		83		50			33
Shares Issued Under the Directors' Stock Plan		114		85			29
Shares Issued Under the Employee Stock Purchase Plan		120		87			33
Shares Issued for Dividend Reinvestment Plans		472		330			142
Stock-Based Compensation Expense		517		517
Purchases of Treasury Stock		(848)					(848)
Stockholders' equity, ending balance at Sep. 30, 2023		360,014	22,067	412,397	62,647	(52,584)	(84,513)
Stockholders' equity, beginning balance at Jun. 30, 2023		361,443	21,424	401,069	71,076	(47,613)	(84,513)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income		7,743			7,743
Other Comprehensive Income (Loss)		(4,971)				(4,971)
Stock Dividend		0	643	11,058	(11,701)
Cash Dividends Paid		(4,471)			(4,471)
Stock-Based Compensation Expense		270		270
Stockholders' equity, ending balance at Sep. 30, 2023		$ 360,014	$ 22,067	$ 412,397	$ 62,647	$ (52,584)	$ (84,513)

[1] Cash dividends paid per share have been adjusted for the September 26, 2023 3% stock dividend.