Consolidated Statements of Changes in Shareholders' Equity (Unaudited) - 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, 2020		56,200,487
Beginning balance at Dec. 31, 2020	$ 2,132,733	$ 296,483	$ (101,554)	$ 1,296,963	$ 615,773	$ 25,068
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	57,908				57,908
Other comprehensive loss	(4,929)					(4,929)
Comprehensive (loss) income	52,979
Cash dividends	(12,564)				(12,564)
Issuance of common stock for stock-based compensation awards (in shares)		93,859
Issuance of common stock for stock-based compensation awards	(2,203)		2,605	(4,808)
Stock-based compensation expense	2,756			2,756
Ending balance (in shares) at Mar. 31, 2021		56,294,346
Ending balance at Mar. 31, 2021	2,173,701	$ 296,483	(98,949)	1,294,911	661,117	20,139
Beginning balance (in shares) at Dec. 31, 2020		56,200,487
Beginning balance at Dec. 31, 2020	2,132,733	$ 296,483	(101,554)	1,296,963	615,773	25,068
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	98,775
Other comprehensive loss	(5,818)
Comprehensive (loss) income	92,957
Ending balance (in shares) at Jun. 30, 2021		56,350,878
Ending balance at Jun. 30, 2021	2,203,807	$ 296,483	(97,249)	1,295,879	689,444	19,250
Beginning balance (in shares) at Mar. 31, 2021		56,294,346
Beginning balance at Mar. 31, 2021	2,173,701	$ 296,483	(98,949)	1,294,911	661,117	20,139
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	40,867				40,867
Other comprehensive loss	(889)					(889)
Comprehensive (loss) income	39,978
Cash dividends	(12,540)				(12,540)
Issuance of common stock for stock-based compensation awards (in shares)		56,532
Issuance of common stock for stock-based compensation awards	283		1,700	(1,417)
Stock-based compensation expense	2,385			2,385
Ending balance (in shares) at Jun. 30, 2021		56,350,878
Ending balance at Jun. 30, 2021	2,203,807	$ 296,483	(97,249)	1,295,879	689,444	19,250
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 loss	(94,126)					(94,126)
Comprehensive (loss) income	(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	73,225
Other comprehensive loss	(144,955)
Comprehensive (loss) income	(71,730)
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)
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 loss	(50,829)					(50,829)
Comprehensive (loss) income	(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)