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	92,821		92,821
Other comprehensive income (loss)	(242,895)			(242,895)
Cash dividends declared :
Common stock at $0.23 per share in 2023 and $0.23 per share in 2022	(43,288)		(43,288)
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)					283,892
Restricted stock awards, net of forfeitures	(2,915)	(8,789)			$ 5,874
Share-based compensation expense	5,828	$ 5,828
Ending Balances (in shares) at Jun. 30, 2022		104,281,794			(9,833,002)
Ending Balances at Jun. 30, 2022	2,068,670	$ 1,637,237	887,006	(243,328)	$ (212,245)
Beginning Balances (in shares) at Mar. 31, 2022		104,281,794			(9,830,298)
Beginning Balances at Mar. 31, 2022	2,137,445	$ 1,634,903	857,178	(142,477)	$ (212,159)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	51,520		51,520
Other comprehensive income (loss)	(100,851)			(100,851)
Cash dividends declared :
Common stock at $0.23 per share in 2023 and $0.23 per share in 2022	(21,692)		(21,692)
Restricted stock awards, net of forfeitures (in shares)					(2,704)
Restricted stock awards, net of forfeitures	(73)	13			$ (86)
Share-based compensation expense	2,321	$ 2,321
Ending Balances (in shares) at Jun. 30, 2022		104,281,794			(9,833,002)
Ending Balances at Jun. 30, 2022	2,068,670	$ 1,637,237	887,006	(243,328)	$ (212,245)
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	136,070		136,070
Other comprehensive income (loss)	5,653			5,653
Cash dividends declared :
Common stock at $0.23 per share in 2023 and $0.23 per share in 2022	(43,592)		(43,592)
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)					289,529
Restricted stock awards, net of forfeitures	(4,924)	(10,680)			$ 5,756
Share-based compensation expense	8,791	$ 8,791
Ending Balances (in shares) at Jun. 30, 2023		104,281,794			(9,096,311)
Ending Balances at Jun. 30, 2023	2,143,419	$ 1,632,659	1,060,715	(353,010)	$ (196,945)
Beginning Balances (in shares) at Mar. 31, 2023		104,281,794			(9,091,388)
Beginning Balances at Mar. 31, 2023	2,121,496	$ 1,629,428	1,016,893	(328,059)	$ (196,766)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	65,667		65,667
Other comprehensive income (loss)	(24,951)			(24,951)
Cash dividends declared :
Common stock at $0.23 per share in 2023 and $0.23 per share in 2022	(21,845)		(21,845)
Exercise of stock options, net of shares purchased (in shares)					1,387
Exercise of stock options, net of shares purchased	(14)	(16)			$ (30)
Restricted stock awards, net of forfeitures (in shares)					(6,310)
Restricted stock awards, net of forfeitures	(1,137)	(928)			$ (209)
Share-based compensation expense	4,175	$ 4,175
Ending Balances (in shares) at Jun. 30, 2023		104,281,794			(9,096,311)
Ending Balances at Jun. 30, 2023	2,143,419	$ 1,632,659	$ 1,060,715	$ (353,010)	$ (196,945)
Retained Earnings (Accumulated Deficit)	$ 1,060,715