Consolidated Statements of Changes in Shareholders' Equity - USD ($) shares in Thousands, $ in Thousands	Common Stock [Member]	Deferred Compensation, Share-Based Payments [Member]	AOCI Attributable to Parent [Member]	Retained Earnings [Member]	Total
Balance (in shares) at Dec. 31, 2020	26,807
Balance at Dec. 31, 2020	$ 466,006	$ 35	$ 114,412	$ 264,356	$ 844,809
Net Income				86,509	86,509
Other comprehensive income (loss)			(64,748)		$ (64,748)
Exercise of stock options (in shares)	53				53
Exercise of stock options	$ 3,017				$ 3,017
Restricted stock activity (in shares)	9
Restricted stock activity	$ 526				526
Stock based compensation	$ 1,419				1,419
Stock awarded to employees (in shares)	1
Stock awarded to employees	$ 106				106
Retirement of common stock (in shares)	(4)
Retirement of common stock	$ (66)			(166)	(232)
Dividends				(44,304)	(44,304)
Balance (in shares) at Dec. 31, 2021	26,866
Balance at Dec. 31, 2021	$ 471,008	35	49,664	306,395	827,102
Net Income				122,034	122,034
Other comprehensive income (loss)			(305,769)		$ (305,769)
Exercise of stock options (in shares)	40				40
Exercise of stock options	$ 2,255				$ 2,255
Restricted stock activity (in shares)	8
Restricted stock activity	$ 492				492
Stock based compensation	$ 1,309				1,309
Stock awarded to employees (in shares)	2
Stock awarded to employees	$ 87				87
Retirement of common stock (in shares)	(3)
Retirement of common stock	$ (65)			(153)	(218)
Dividends				(45,182)	(45,182)
Balance (in shares) at Dec. 31, 2022	26,913
Balance at Dec. 31, 2022	$ 475,086	35	(256,105)	383,094	602,110
Net Income				161,768	161,768
Other comprehensive income (loss)			65,823		$ 65,823
Exercise of stock options (in shares)	22				22
Exercise of stock options	$ 950				$ 950
Restricted stock activity (in shares)	9
Restricted stock activity	$ 508				508
Stock based compensation	$ 1,356				1,356
Stock awarded to employees (in shares)	1
Stock awarded to employees	$ 80				80
Retirement of common stock (in shares)	(274)
Retirement of common stock	$ (4,844)			(8,903)	(13,747)
Dividends				(45,954)	(45,954)
Balance (in shares) at Dec. 31, 2023	26,671
Balance at Dec. 31, 2023	$ 473,136	$ 35	$ (190,282)	$ 490,005	$ 772,894