Consolidated Statements of Changes in Shareholders' Equity (Unaudited) - USD ($) $ in Thousands	Total	Common Stock [Member]	Capital Surplus [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]
Balance at Dec. 31, 2022	$ 1,492,268	$ 12,705	$ 154,645	$ 1,600,321	$ (275,403)
Balance (in shares) at Dec. 31, 2022		60,977,686
Net Income (Loss)	50,300			50,300
Other comprehensive income (loss), net of tax	33,022				33,022
Common stock dividends paid ($0.23 per share)	(14,158)			(14,158)
Shares withheld to pay taxes, long-term incentive plan	(1,048)	$ 15	(1,063)
Shares withheld to pay taxes, long-term incentive plan (in shares)		70,830
Compensation expense, long-term incentive plan	1,715		1,715
Balance at Mar. 31, 2023	1,562,099	$ 12,720	155,297	1,636,463	(242,381)
Balance (in shares) at Mar. 31, 2023		61,048,516
Balance at Dec. 31, 2022	1,492,268	$ 12,705	154,645	1,600,321	(275,403)
Balance (in shares) at Dec. 31, 2022		60,977,686
Net Income (Loss)	129,366
Other comprehensive income (loss), net of tax	(12,485)
Balance at Sep. 30, 2023	1,570,351	$ 12,724	158,316	1,687,199	(287,888)
Balance (in shares) at Sep. 30, 2023		61,070,095
Balance at Mar. 31, 2023	1,562,099	$ 12,720	155,297	1,636,463	(242,381)
Balance (in shares) at Mar. 31, 2023		61,048,516
Net Income (Loss)	45,037			45,037
Other comprehensive income (loss), net of tax	(23,323)				(23,323)
Common stock dividends paid ($0.23 per share)	(14,161)			(14,161)
Shares withheld to pay taxes, long-term incentive plan	(22)	$ 4	(26)
Shares withheld to pay taxes, long-term incentive plan (in shares)		20,520
Compensation expense, long-term incentive plan	1,563		1,563
Balance at Jun. 30, 2023	1,571,193	$ 12,724	156,834	1,667,339	(265,704)
Balance (in shares) at Jun. 30, 2023		61,069,036
Net Income (Loss)	34,029			34,029
Other comprehensive income (loss), net of tax	(22,184)				(22,184)
Common stock dividends paid ($0.23 per share)	(14,169)			(14,169)
Shares withheld to pay taxes, long-term incentive plan	(12)		(12)
Shares withheld to pay taxes, long-term incentive plan (in shares)		1,059
Compensation expense, long-term incentive plan	1,494		1,494
Balance at Sep. 30, 2023	1,570,351	$ 12,724	158,316	1,687,199	(287,888)
Balance (in shares) at Sep. 30, 2023		61,070,095
Balance at Dec. 31, 2023	$ 1,661,847	$ 12,725	159,688	1,709,157	(219,723)
Balance (in shares) at Dec. 31, 2023	61,071,173	61,071,173
Net Income (Loss)	$ 41,535			41,535
Other comprehensive income (loss), net of tax	(7,431)				(7,431)
Common stock dividends paid ($0.23 per share)	(14,207)			(14,207)
Shares withheld to pay taxes, long-term incentive plan	(1,383)	$ 22	(1,405)
Shares withheld to pay taxes, long-term incentive plan (in shares)		107,193
Compensation expense, long-term incentive plan	2,238		2,238
Balance at Mar. 31, 2024	1,682,599	$ 12,747	160,521	1,736,485	(227,154)
Balance (in shares) at Mar. 31, 2024		61,178,366
Balance at Dec. 31, 2023	$ 1,661,847	$ 12,725	159,688	1,709,157	(219,723)
Balance (in shares) at Dec. 31, 2023	61,071,173	61,071,173
Net Income (Loss)	$ 166,697
Other comprehensive income (loss), net of tax	190,678
Balance at Sep. 30, 2024	$ 1,980,096	$ 12,753	163,156	1,833,232	(29,045)
Balance (in shares) at Sep. 30, 2024	61,206,606	61,206,606
Balance at Mar. 31, 2024	$ 1,682,599	$ 12,747	160,521	1,736,485	(227,154)
Balance (in shares) at Mar. 31, 2024		61,178,366
Net Income (Loss)	73,832			73,832
Other comprehensive income (loss), net of tax	135,597				135,597
Common stock dividends paid ($0.23 per share)	(14,206)			(14,206)
Shares withheld to pay taxes, long-term incentive plan	(59)	$ 6	(65)
Shares withheld to pay taxes, long-term incentive plan (in shares)		27,603
Compensation expense, long-term incentive plan	1,378		1,378
Balance at Jun. 30, 2024	1,879,141	$ 12,753	161,834	1,796,111	(91,557)
Balance (in shares) at Jun. 30, 2024		61,205,969
Net Income (Loss)	51,330			51,330
Other comprehensive income (loss), net of tax	62,512				62,512
Common stock dividends paid ($0.23 per share)	(14,209)			(14,209)
Shares withheld to pay taxes, long-term incentive plan	(8)		(8)
Shares withheld to pay taxes, long-term incentive plan (in shares)		637
Compensation expense, long-term incentive plan	1,330		1,330
Balance at Sep. 30, 2024	$ 1,980,096	$ 12,753	$ 163,156	$ 1,833,232	$ (29,045)
Balance (in shares) at Sep. 30, 2024	61,206,606	61,206,606