CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY (UNAUDITED) - USD ($) $ in Thousands	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Treasury Stock [Member]	Total
Beginning balance at Dec. 31, 2019	$ 5,447	$ 51,165	$ 86,751	$ 528	$ (15,712)	$ 128,179
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	0	0	5,559	0	0	5,559
Other comprehensive income (loss), net	0	0	0	2,176	0	2,176
Cash dividends, $.63 per share	0	0	(3,016)	0	0	(3,016)
Ending balance at Sep. 30, 2020	5,447	51,165	89,294	2,704	(15,712)	132,898
Beginning balance at Jun. 30, 2020	5,447	51,165	88,006	2,915	(15,712)	131,821
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	0	0	2,294	0	0	2,294
Other comprehensive income (loss), net	0	0	0	(211)	0	(211)
Cash dividends, $.63 per share	0	0	(1,006)	0	0	(1,006)
Ending balance at Sep. 30, 2020	5,447	51,165	89,294	2,704	(15,712)	132,898
Beginning balance at Dec. 31, 2020	5,447	51,165	92,988	2,436	(15,712)	136,324
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	0	0	9,428	0	0	9,428
Other comprehensive income (loss), net	0	0	0	(1,348)	0	(1,348)
Cash dividends, $.63 per share	0	0	(3,016)	0	0	(3,016)
Shares acquired for treasury, 16,569 shares	0	0	0	0	(458)	(458)
Ending balance at Sep. 30, 2021	5,447	51,165	99,400	1,088	(16,170)	140,930
Beginning balance at Jun. 30, 2021	5,447	51,165	97,369	1,155	(15,712)	139,424
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	0	0	3,036	0	0	3,036
Other comprehensive income (loss), net	0	0	0	(67)	0	(67)
Cash dividends, $.63 per share	0	0	(1,005)	0	0	(1,005)
Shares acquired for treasury, 16,569 shares	0	0	0	0	(458)	(458)
Ending balance at Sep. 30, 2021	$ 5,447	$ 51,165	$ 99,400	$ 1,088	$ (16,170)	$ 140,930