CONSOLIDATED STATEMENTS OF CHANGES IN SHAREHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Common Stock	Retained earnings	Accumulated other comprehensive income (loss)	Treasury Stock, Common
Beginning Balances (in shares) at Dec. 31, 2021		104,281,794			(10,132,554)
Beginning Balances at Dec. 31, 2021	$ 2,258,942	$ 1,640,358	$ 837,473	$ (433)	$ (218,456)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	148,526		148,526
Other comprehensive income (loss)	(354,137)			(354,137)
Cash dividends declared :
Common stock at $0.23 per share in 2023 and $0.23 per share in 2022	(65,056)		(65,056)
Exercise of stock options, net of shares purchased (in shares)					15,660
Exercise of stock options, net of shares purchased	(177)	(160)			$ (337)
Restricted stock awards, net of forfeitures (in shares)					669,064
Restricted stock awards, net of forfeitures	(3,027)	(17,209)			$ 14,182
Share-based compensation expense	8,707	$ 8,707
Ending Balances (in shares) at Sep. 30, 2022		104,281,794			(9,447,830)
Ending Balances at Sep. 30, 2022	1,994,132	$ 1,631,696	920,943	(354,570)	$ (203,937)
Beginning Balances (in shares) at Jun. 30, 2022		104,281,794			(9,833,002)
Beginning Balances at Jun. 30, 2022	2,068,670	$ 1,637,237	887,006	(243,328)	$ (212,245)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	55,705		55,705
Other comprehensive income (loss)	(111,242)			(111,242)
Cash dividends declared :
Common stock at $0.23 per share in 2023 and $0.23 per share in 2022	(21,768)		(21,768)
Restricted stock awards, net of forfeitures (in shares)					385,172
Restricted stock awards, net of forfeitures	(112)	(8,420)			$ 8,308
Share-based compensation expense	2,879	$ 2,879
Ending Balances (in shares) at Sep. 30, 2022		104,281,794			(9,447,830)
Ending Balances at Sep. 30, 2022	1,994,132	$ 1,631,696	920,943	(354,570)	$ (203,937)
Retained Earnings (Accumulated Deficit)	968,237
Beginning Balances (in shares) at Dec. 31, 2022		104,281,794			(9,390,695)
Beginning Balances at Dec. 31, 2022	2,041,373	$ 1,634,605	968,237	(358,663)	$ (202,806)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	199,131		199,131
Other comprehensive income (loss)	(51,342)			(51,342)
Cash dividends declared :
Common stock at $0.23 per share in 2023 and $0.23 per share in 2022	(65,463)		(65,463)
Exercise of stock options, net of shares purchased (in shares)					4,855
Exercise of stock options, net of shares purchased	(48)	(57)			$ (105)
Restricted stock awards, net of forfeitures (in shares)					221,226
Restricted stock awards, net of forfeitures	(7,589)	(11,845)			$ 4,256
Share-based compensation expense	13,351	$ 13,351
Ending Balances (in shares) at Sep. 30, 2023		104,281,794			(9,164,614)
Ending Balances at Sep. 30, 2023	2,129,509	$ 1,636,054	1,101,905	(410,005)	$ (198,445)
Beginning Balances (in shares) at Jun. 30, 2023		104,281,794			(9,096,311)
Beginning Balances at Jun. 30, 2023	2,143,419	$ 1,632,659	1,060,715	(353,010)	$ (196,945)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	63,061		63,061
Other comprehensive income (loss)	(56,995)			(56,995)
Cash dividends declared :
Common stock at $0.23 per share in 2023 and $0.23 per share in 2022	(21,871)		(21,871)
Restricted stock awards, net of forfeitures (in shares)					(68,303)
Restricted stock awards, net of forfeitures	(2,665)	(1,165)			$ (1,500)
Share-based compensation expense	4,560	$ 4,560
Ending Balances (in shares) at Sep. 30, 2023		104,281,794			(9,164,614)
Ending Balances at Sep. 30, 2023	2,129,509	$ 1,636,054	$ 1,101,905	$ (410,005)	$ (198,445)
Retained Earnings (Accumulated Deficit)	$ 1,101,905