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, 2021	$ 1,741,311	$ 12,845	$ 175,913	$ 1,585,113	$ (32,560)
Balance (in shares) at Dec. 31, 2021		61,648,679
Net Income (Loss)	29,211			29,211
Other comprehensive income (loss), net of tax	(116,096)				(116,096)
Common stock dividends paid ($0.23 per share)	(14,186)			(14,186)
Shares withheld to pay taxes, long-term incentive plan	(1,009)	$ 19	(1,028)
Shares withheld to pay taxes, long-term incentive plan (in shares)		93,944
Repurchase and retirement of common stock	(9,094)	$ (58)	(9,036)
Repurchase and retirement of common stock (in shares)		(279,231)
Compensation expense, long-term incentive plan	1,245		1,245
Balance at Mar. 31, 2022	1,631,382	$ 12,806	167,094	1,600,138	(148,656)
Balance (in shares) at Mar. 31, 2022		61,463,392
Balance at Dec. 31, 2021	1,741,311	$ 12,845	175,913	1,585,113	(32,560)
Balance (in shares) at Dec. 31, 2021		61,648,679
Net Income (Loss)	105,950
Other comprehensive income (loss), net of tax	(273,852)
Balance at Sep. 30, 2022	1,508,945	$ 12,700	154,150	1,648,507	(306,412)
Balance (in shares) at Sep. 30, 2022		60,953,864
Balance at Mar. 31, 2022	1,631,382	$ 12,806	167,094	1,600,138	(148,656)
Balance (in shares) at Mar. 31, 2022		61,463,392
Net Income (Loss)	34,284			34,284
Other comprehensive income (loss), net of tax	(58,486)				(58,486)
Common stock dividends paid ($0.23 per share)	(14,212)			(14,212)
Shares withheld to pay taxes, long-term incentive plan	(7)		(7)
Shares withheld to pay taxes, long-term incentive plan (in shares)		513
Repurchase and retirement of common stock	(7,505)	$ (54)	(7,451)
Repurchase and retirement of common stock (in shares)		(262,782)
Compensation expense, long-term incentive plan	1,240		1,240
Balance at Jun. 30, 2022	1,586,696	$ 12,752	160,876	1,620,210	(207,142)
Balance (in shares) at Jun. 30, 2022		61,201,123
Net Income (Loss)	42,455			42,455
Other comprehensive income (loss), net of tax	(99,270)				(99,270)
Common stock dividends paid ($0.23 per share)	(14,158)			(14,158)
Shares withheld to pay taxes, long-term incentive plan	(2)		(2)
Shares withheld to pay taxes, long-term incentive plan (in shares)		119
Repurchase and retirement of common stock	(8,005)	$ (52)	(7,953)
Repurchase and retirement of common stock (in shares)		(247,378)
Compensation expense, long-term incentive plan	1,229		1,229
Balance at Sep. 30, 2022	1,508,945	$ 12,700	154,150	1,648,507	(306,412)
Balance (in shares) at Sep. 30, 2022		60,953,864
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	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	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	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	61,070,095