Consolidated Statements of Changes in Shareholders' Equity (Unaudited) - USD ($) $ in Thousands	Capital Stock [Member]	Surplus [Member]	Undivided Profits [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Treasury Stock [Member]	Total
Balance at Dec. 31, 2023	$ 20,058	$ 257,181	$ 425,069	$ (13,237)	$ (43,786)	$ 645,285
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	0	0	12,126	0	0	12,126
Other comprehensive income (loss), net of tax	0	0	0	(1,526)	0	(1,526)
Stock Based Compensation Expense	0	154	0	0	0	154
Cash dividend declared	0	0	(6,849)	0	0	(6,849)
Balance at Mar. 31, 2024	20,058	257,335	430,346	(14,763)	(43,786)	649,190
Balance at Dec. 31, 2023	20,058	257,181	425,069	(13,237)	(43,786)	645,285
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income						24,677
Other comprehensive income (loss), net of tax						(1,031)
Balance at Jun. 30, 2024	20,058	257,490	436,048	(14,268)	(44,160)	655,168
Balance at Mar. 31, 2024	20,058	257,335	430,346	(14,763)	(43,786)	649,190
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	0	0	12,551	0	0	12,551
Other comprehensive income (loss), net of tax	0	0	0	495	0	495
Stock Based Compensation Expense	0	155	0	0	0	155
Cash dividend declared	0	0	(6,849)	0	0	(6,849)
Purchase of treasury stock	0	0	0	0	(374)	(374)
Balance at Jun. 30, 2024	20,058	257,490	436,048	(14,268)	(44,160)	655,168
Balance at Dec. 31, 2024	20,097	258,874	446,503	(3,861)	(45,270)	676,343
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	0	0	14,275	0	0	14,275
Other comprehensive income (loss), net of tax	0	0	0	3,729	0	3,729
Stock Based Compensation Expense	0	308	0	0	0	308
Cash dividend declared	0	0	(6,847)	0	0	(6,847)
Balance at Mar. 31, 2025	20,097	259,182	453,931	(132)	(45,270)	687,808
Balance at Dec. 31, 2024	20,097	258,874	446,503	(3,861)	(45,270)	676,343
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income						29,314
Other comprehensive income (loss), net of tax						5,524
Balance at Jun. 30, 2025	20,097	259,490	462,158	1,663	(50,603)	692,805
Balance at Mar. 31, 2025	20,097	259,182	453,931	(132)	(45,270)	687,808
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	0	0	15,039	0	0	15,039
Other comprehensive income (loss), net of tax	0	0	0	1,795	0	1,795
Stock Based Compensation Expense	0	308	0	0	0	308
Cash dividend declared	0	0	(6,812)	0	0	(6,812)
Purchase of treasury stock	0	0	0	0	(5,333)	(5,333)
Balance at Jun. 30, 2025	$ 20,097	$ 259,490	$ 462,158	$ 1,663	$ (50,603)	$ 692,805