Consolidated Statements of Changes in Shareholders' Equity - USD ($) $ in Thousands	Total	Common Stock	Treasury Stock	Additional Paid-In Capital	Retained Earnings	Accumulated Other Comprehensive Income (Loss)
Beginning balance (in shares) at Dec. 31, 2021		55,756,233
Beginning balance at Dec. 31, 2021	$ 2,209,853	$ 296,483	$ (118,027)	$ 1,300,192	$ 741,648	$ (10,443)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	33,547				33,547
Other comprehensive income (loss)	(94,126)					(94,126)
Comprehensive income (loss)	(60,579)
Cash dividends	(12,505)				(12,505)
Issuance of common stock for stock-based compensation awards (in shares)		124,433
Issuance of common stock for stock-based compensation awards	(2,465)		3,977	(6,442)
Stock-based compensation expense	3,338			3,338
Ending balance (in shares) at Mar. 31, 2022		55,880,666
Ending balance at Mar. 31, 2022	2,137,642	$ 296,483	(114,050)	1,297,088	762,690	(104,569)
Beginning balance (in shares) at Dec. 31, 2021		55,756,233
Beginning balance at Dec. 31, 2021	2,209,853	$ 296,483	(118,027)	1,300,192	741,648	(10,443)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	119,792
Other comprehensive income (loss)	(205,609)
Comprehensive income (loss)	(85,817)
Ending balance (in shares) at Sep. 30, 2022		55,953,104
Ending balance at Sep. 30, 2022	2,092,281	$ 296,483	(111,577)	1,299,476	823,951	(216,052)
Beginning balance (in shares) at Mar. 31, 2022		55,880,666
Beginning balance at Mar. 31, 2022	2,137,642	$ 296,483	(114,050)	1,297,088	762,690	(104,569)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	39,678				39,678
Other comprehensive income (loss)	(50,829)					(50,829)
Comprehensive income (loss)	(11,151)
Cash dividends	(12,488)				(12,488)
Issuance of common stock for stock-based compensation awards (in shares)		51,351
Issuance of common stock for stock-based compensation awards	(78)		1,755	(1,833)
Stock-based compensation expense	2,952			2,952
Ending balance (in shares) at Jun. 30, 2022		55,932,017
Ending balance at Jun. 30, 2022	2,116,877	$ 296,483	(112,295)	1,298,207	789,880	(155,398)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	46,567				46,567
Other comprehensive income (loss)	(60,654)					(60,654)
Comprehensive income (loss)	(14,087)
Cash dividends	(12,496)				(12,496)
Issuance of common stock for stock-based compensation awards (in shares)		21,087
Issuance of common stock for stock-based compensation awards	(282)		718	(1,000)
Stock-based compensation expense	2,269			2,269
Ending balance (in shares) at Sep. 30, 2022		55,953,104
Ending balance at Sep. 30, 2022	$ 2,092,281	$ 296,483	(111,577)	1,299,476	823,951	(216,052)
Beginning balance (in shares) at Dec. 31, 2022	55,953,104	55,953,104
Beginning balance at Dec. 31, 2022	$ 2,136,016	$ 296,483	(111,577)	1,302,422	857,725	(209,037)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	46,078				46,078
Other comprehensive income (loss)	16,713					16,713
Comprehensive income (loss)	62,791
Cash dividends	(12,561)				(12,561)
Issuance of common stock for stock-based compensation awards (in shares)		120,554
Issuance of common stock for stock-based compensation awards	(2,391)		4,018	(6,409)
Stock-based compensation expense	3,445			3,445
Ending balance (in shares) at Mar. 31, 2023		56,073,658
Ending balance at Mar. 31, 2023	$ 2,187,300	$ 296,483	(107,559)	1,299,458	891,242	(192,324)
Beginning balance (in shares) at Dec. 31, 2022	55,953,104	55,953,104
Beginning balance at Dec. 31, 2022	$ 2,136,016	$ 296,483	(111,577)	1,302,422	857,725	(209,037)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	116,554
Other comprehensive income (loss)	9,713
Comprehensive income (loss)	$ 126,267
Ending balance (in shares) at Sep. 30, 2023	56,140,713	56,140,713
Ending balance at Sep. 30, 2023	$ 2,233,323	$ 296,483	(105,300)	1,304,891	936,573	(199,324)
Beginning balance (in shares) at Mar. 31, 2023		56,073,658
Beginning balance at Mar. 31, 2023	2,187,300	$ 296,483	(107,559)	1,299,458	891,242	(192,324)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	28,643				28,643
Other comprehensive income (loss)	863					863
Comprehensive income (loss)	29,506
Cash dividends	(12,573)				(12,573)
Issuance of common stock for stock-based compensation awards (in shares)		58,820
Issuance of common stock for stock-based compensation awards	1,000		1,970	(970)
Stock-based compensation expense	3,395			3,395
Ending balance (in shares) at Jun. 30, 2023		56,132,478
Ending balance at Jun. 30, 2023	2,208,628	$ 296,483	(105,589)	1,301,883	907,312	(191,461)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	41,833				41,833
Other comprehensive income (loss)	(7,863)					(7,863)
Comprehensive income (loss)	33,970
Cash dividends	(12,572)				(12,572)
Issuance of common stock for stock-based compensation awards (in shares)		8,235
Issuance of common stock for stock-based compensation awards	(127)		289	(416)
Stock-based compensation expense	$ 3,424			3,424
Ending balance (in shares) at Sep. 30, 2023	56,140,713	56,140,713
Ending balance at Sep. 30, 2023	$ 2,233,323	$ 296,483	$ (105,300)	$ 1,304,891	$ 936,573	$ (199,324)