Consolidated Statements of Changes in Stockholders' Equity (unaudited) - USD ($) $ in Thousands	Common Stock [Member]	Additional Paid-in-Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive (Loss) Income [Member]	Common Stock in Treasury [Member]	Total
Balance at Dec. 31, 2023	$ 540	$ 740,943	$ 1,021,831	$ (160,934)	$ (176,689)	$ 1,425,691
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	0	0	104,636	0	0	104,636
Cash dividends	0	0	(46,222)	0	0	(46,222)
Purchase of treasury shares	0	0	0	0	(251)	(251)
Net issuance of shares to employee and other stock plans	0	(3,574)	0	0	1,347	(2,227)
Stock-based compensation	0	5,155	0	0	0	5,155
Other comprehensive income	0	0	0	35,198	0	35,198
Balance at Sep. 30, 2024	540	742,524	1,080,245	(125,736)	(175,593)	1,521,980
Balance at Jun. 30, 2024	540	741,933	1,058,187	(162,919)	(175,786)	1,461,955
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	0	0	38,097	0	0	38,097
Cash dividends	0	0	(16,039)	0	0	(16,039)
Net issuance of shares to employee and other stock plans	0	(373)	0	0	193	(180)
Stock-based compensation	0	964	0	0	0	964
Other comprehensive income	0	0	0	37,183	0	37,183
Balance at Sep. 30, 2024	540	742,524	1,080,245	(125,736)	(175,593)	1,521,980
Balance at Dec. 31, 2024	540	742,810	1,100,209	(142,098)	(175,320)	1,526,141
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	0	0	113,726	0	0	113,726
Cash dividends	0	0	(53,279)	0	0	(53,279)
Issuance of common stock for acquisition	51	221,716	0	0	0	221,767
Net issuance of shares to employee and other stock plans	0	(5,044)	0	0	1,983	(3,061)
Stock-based compensation	0	4,634	0	0	0	4,634
Other comprehensive income	0	0	0	43,218	0	43,218
Balance at Sep. 30, 2025	591	964,116	1,160,656	(98,880)	(173,337)	1,853,146
Balance at Jun. 30, 2025	591	962,868	1,125,589	(109,488)	(174,394)	1,805,166
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	0	0	54,471	0	0	54,471
Cash dividends	0	0	(19,404)	0	0	(19,404)
Net issuance of shares to employee and other stock plans	0	(339)	0	0	1,057	718
Stock-based compensation	0	1,587	0	0	0	1,587
Other comprehensive income	0	0	0	10,608	0	10,608
Balance at Sep. 30, 2025	$ 591	$ 964,116	$ 1,160,656	$ (98,880)	$ (173,337)	$ 1,853,146