CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY - UNAUDITED - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Retained Earnings	Accumulated Other Comprehensive Income/ (Loss)
Balance at beginning of period at Dec. 31, 2021	$ 1,519,679	$ 45,119	$ 751,072	$ 732,027	$ (8,539)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	98,735			98,735
Other comprehensive loss, net of tax	(88,914)				(88,914)
Comprehensive income	9,821
Common stock dividends	(31,055)			(31,055)
Stock compensation expense	4,650		4,650
Stock option plan	240	10	230
Employee stock purchase plan	930	22	908
Restricted stock vesting, net of tax withholding	(2,109)	104	(2,213)
Repurchase of common stock	(24,987)	(625)	(24,362)
Balance at end of period at Jun. 30, 2022	1,477,169	44,630	730,285	799,707	(97,453)
Balance at beginning of period at Mar. 31, 2022	1,488,910	45,163	752,671	760,347	(69,271)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	54,800			54,800
Other comprehensive loss, net of tax	(28,182)				(28,182)
Comprehensive income	26,618
Common stock dividends	(15,440)			(15,440)
Stock compensation expense	3,178		3,178
Stock option plan	45	1	44
Employee stock purchase plan	494	12	482
Restricted stock vesting, net of tax withholding	(1,649)	79	(1,728)
Repurchase of common stock	(24,987)	(625)	(24,362)
Balance at end of period at Jun. 30, 2022	1,477,169	44,630	730,285	799,707	(97,453)
Balance at beginning of period at Dec. 31, 2022	1,483,768	44,657	734,273	836,789	(131,951)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	75,998			75,998
Other comprehensive loss, net of tax	6,326				6,326
Comprehensive income	82,324
Common stock dividends	(30,732)			(30,732)
Stock compensation expense	3,972		3,972
Stock option plan	517	41	476
Employee stock purchase plan	844	31	813
Restricted stock vesting, net of tax withholding	(1,661)	133	(1,794)
Balance at end of period at Jun. 30, 2023	1,539,032	44,862	737,740	882,055	(125,625)
Balance at beginning of period at Mar. 31, 2023	1,536,865	44,712	735,509	872,635	(115,991)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	24,745			24,745
Other comprehensive loss, net of tax	(9,634)				(9,634)
Comprehensive income	15,111
Common stock dividends	(15,325)			(15,325)
Stock compensation expense	2,731		2,731
Stock option plan	366	34	332
Employee stock purchase plan	433	19	414
Restricted stock vesting, net of tax withholding	(1,149)	97	(1,246)
Balance at end of period at Jun. 30, 2023	$ 1,539,032	$ 44,862	$ 737,740	$ 882,055	$ (125,625)