Stockholders Equity (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended						9 Months Ended
	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Sep. 30, 2021	Jun. 30, 2021	Mar. 31, 2021	Sep. 30, 2022	Sep. 30, 2021
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance at beginning of period	$ 1,320,094	$ 1,441,030	$ 1,428,766	$ 1,390,393	$ 1,351,367	$ 1,382,677	$ 1,428,766	$ 1,382,677
Comprehensive income (loss)	(47,800)	(109,514)	17,894	6,182	49,082	(25,520)	(139,420)	29,744
Dividends declared	(8,090)	(8,081)	(8,111)	(8,099)	(8,090)	(8,104)
Common stock repurchases		(6,721)			(5,229)
Residual interest in subsidiary				2,177
Employee stock plans	2,852	3,380	2,481	2,576	3,263	2,314
Balance at end of period	$ 1,267,056	$ 1,320,094	$ 1,441,030	$ 1,393,229	$ 1,390,393	$ 1,351,367	$ 1,267,056	$ 1,393,229
Dividends declared (in dollars per share)	$ 0.16	$ 0.16		$ 0.16	$ 0.16
Common Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance at beginning of period (in shares)	64,379	64,356	64,344	64,200	64,183	64,171	64,344	64,171
Balance at beginning of period	$ 644	$ 644	$ 643	$ 642	$ 642	$ 642	$ 643	$ 642
Employee stock plans (in shares)	70	23	12	84	17	12
Employee stock plans	$ 0		$ 1	$ 1
Balance at end of period (in shares)	64,449	64,379	64,356	64,284	64,200	64,183	64,449	64,284
Balance at end of period	$ 644	$ 644	$ 644	$ 643	$ 642	$ 642	$ 644	$ 643
Additional Paid-In Capital
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance at beginning of period	522,775	519,227	516,562	507,354	503,937	501,531	516,562	501,531
Residual interest in subsidiary				2,177
Employee stock plans	3,592	3,548	2,665	3,826	3,417	2,406
Balance at end of period	$ 526,367	$ 522,775	$ 519,227	$ 513,357	$ 507,354	$ 503,937	$ 526,367	$ 513,357
Treasury Stock
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance at beginning of period (in shares)	13,863	13,660	13,658	13,634	13,531	13,530	13,658	13,530
Balance at beginning of period	$ (530,518)	$ (523,691)	$ (523,642)	$ (522,412)	$ (517,060)	$ (516,992)	$ (523,642)	$ (516,992)
Common stock repurchases (in shares)		200			100
Common stock repurchases		$ (6,721)			$ (5,229)
Employee stock plans (in shares)	19	3	2	23	3	1
Employee stock plans	$ (663)	$ (106)	$ (49)	$ (1,165)	$ (123)	$ (68)
Balance at end of period (in shares)	13,882	13,863	13,660	13,657	13,634	13,531	13,882	13,657
Balance at end of period	$ (531,181)	$ (530,518)	$ (523,691)	$ (523,577)	$ (522,412)	$ (517,060)	$ (531,181)	$ (523,577)
Retained Earnings
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance at beginning of period	1,551,583	1,599,278	1,587,041	1,547,435	1,531,065	1,519,811	1,587,041	1,519,811
Comprehensive income (loss)	16,979	(39,552)	20,484	27,863	24,491	19,382
Dividends declared	(8,090)	(8,081)	(8,111)	(8,099)	(8,090)	(8,104)
Employee stock plans	(77)	(62)	(136)	(86)	(31)	(24)
Balance at end of period	1,560,395	1,551,583	1,599,278	1,567,113	1,547,435	1,531,065	1,560,395	1,567,113
Accumulated Other Non-Owner Changes to Equity
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance at beginning of period	(224,390)	(154,428)	(151,838)	(142,626)	(167,217)	(122,315)	(151,838)	(122,315)
Comprehensive income (loss)	(64,779)	(69,962)	(2,590)	(21,681)	24,591	(44,902)
Balance at end of period	$ (289,169)	$ (224,390)	$ (154,428)	$ (164,307)	$ (142,626)	$ (167,217)	$ (289,169)	$ (164,307)