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 per consolidated statements of income	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, 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 per consolidated statements of income	$ 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	61,048,516