Stockholders Equity (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2024	Jun. 30, 2024	Mar. 31, 2024	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Sep. 30, 2024	Sep. 30, 2023
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance at beginning of period	$ 1,276,498	$ 1,331,349	$ 1,362,263	$ 1,376,987	$ 1,380,548	$ 1,346,327	$ 1,362,263	$ 1,346,327
Comprehensive income (loss)	33,384	(49,554)	(26,123)	(34,659)	2,399	42,368	(42,292)	10,107
Dividends declared	(8,132)	(8,118)	(8,111)	(8,107)	(8,099)	(8,096)
Residual interest in subsidiary						(2,381)
Employee stock plans	2,736	2,821	3,320	2,830	2,139	2,330
Balance at end of period	$ 1,304,486	$ 1,276,498	$ 1,331,349	$ 1,337,051	$ 1,376,987	$ 1,380,548	$ 1,304,486	$ 1,337,051
Dividends declared (in dollars per share)	$ 0.16	$ 0.16	$ 0.16	$ 0.16	$ 0.16	$ 0.16
Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance at beginning of period (in shares)	64,679	64,616	64,600	64,526	64,504	64,481	64,600	64,481
Balance at beginning of period	$ 647	$ 646	$ 646	$ 645	$ 645	$ 645	$ 646	$ 645
Employee stock plans (in shares)	110	63	16	59	22	23
Employee stock plans	$ 1	$ 1		$ 1		$ 0
Balance at end of period (in shares)	64,789	64,679	64,616	64,585	64,526	64,504	64,789	64,585
Balance at end of period	$ 648	$ 647	$ 646	$ 646	$ 645	$ 645	$ 648	$ 646
Additional Paid-In Capital
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance at beginning of period	544,418	541,391	537,948	532,414	530,075	529,791	537,948	529,791
Residual interest in subsidiary						(2,381)
Employee stock plans	4,044	3,027	3,443	3,363	2,339	2,665
Balance at end of period	$ 548,462	$ 544,418	$ 541,391	$ 535,777	$ 532,414	$ 530,075	$ 548,462	$ 535,777
Treasury Stock, Common
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance at beginning of period (in shares)	13,918	13,916	13,914	13,900	13,897	13,891	13,914	13,891
Balance at beginning of period	$ (532,556)	$ (532,486)	$ (532,415)	$ (531,883)	$ (531,759)	$ (531,507)	$ (532,415)	$ (531,507)
Employee stock plans (in shares)	32	2	2	12	3	6
Employee stock plans	$ (1,250)	$ (70)	$ (71)	$ (481)	$ (124)	$ (252)
Balance at end of period (in shares)	13,950	13,918	13,916	13,912	13,900	13,897	13,950	13,912
Balance at end of period	$ (533,806)	$ (532,556)	$ (532,486)	$ (532,364)	$ (531,883)	$ (531,759)	$ (533,806)	$ (532,364)
Retained Earnings
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance at beginning of period	1,489,921	1,544,997	1,551,213	1,582,055	1,572,878	1,567,898	1,551,213	1,567,898
Comprehensive income (loss)	(2,144)	(46,821)	1,947	(21,730)	17,352	13,159
Dividends declared	(8,132)	(8,118)	(8,111)	(8,107)	(8,099)	(8,096)
Employee stock plans	(59)	(137)	(52)	(53)	(76)	(83)
Balance at end of period	1,479,586	1,489,921	1,544,997	1,552,165	1,582,055	1,572,878	1,479,586	1,552,165
Accumulated Other Non-Owner Changes to Equity
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance at beginning of period	(225,932)	(223,199)	(195,129)	(206,244)	(191,291)	(220,500)	(195,129)	(220,500)
Comprehensive income (loss)	35,528	(2,733)	(28,070)	(12,929)	(14,953)	29,209
Balance at end of period	$ (190,404)	$ (225,932)	$ (223,199)	$ (219,173)	$ (206,244)	$ (191,291)	$ (190,404)	$ (219,173)