Condensed Consolidated Statements of Changes in Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Accumulated Other Comprehensive Loss, Net	Accumulated Earnings	Treasury Stock
Beginning balance at Dec. 31, 2019	$ 938,593	$ 82	$ 1,899,273	$ (77,938)	$ 1,988,722	$ (2,871,546)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	75,097				75,097
Other comprehensive income (loss)	(91,034)			(91,034)
Issuances under stock plans	5,654		(1,794)			7,448
Common share repurchases	(63,164)					(63,164)
Stock-based compensation expense	25,129		25,129
Ending balance at Mar. 31, 2020	890,275	82	1,922,608	(168,972)	2,063,819	(2,927,262)
Beginning balance at Dec. 31, 2020	1,090,428	82	1,968,930	(99,228)	2,255,467	(3,034,823)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	164,100				164,100
Other comprehensive income (loss)	6,050			6,050
Issuances under stock plans	5,380		(1,543)			6,923
Common share repurchases	(410,450)					(410,450)
Stock-based compensation expense	36,086		36,086
Ending balance at Mar. 31, 2021	$ 891,594	$ 82	$ 2,003,473	$ (93,178)	$ 2,419,567	$ (3,438,350)