CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-In Capital	Treasury Stock	Retained Earnings	Accumulated Other Comprehensive Loss
Beginning balance at Dec. 31, 2020	$ 610,144	$ 441,369	$ 1,842,680	$ (2,282,939)	$ 1,553,610	$ (944,576)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(112,385)				(112,385)
Other comprehensive income (loss), net of tax	(16,450)					(16,450)
Issuance of treasury stock for stock option exercises	1,110		(803)	1,913
Issuance of treasury stock for restricted stock units vesting	(6,966)		(20,031)	13,065
Share-based compensation	15,112		15,112
Ending balance at Mar. 31, 2021	490,565	441,369	1,836,958	(2,267,961)	1,441,225	(961,026)
Beginning balance at Dec. 31, 2020	610,144	441,369	1,842,680	(2,282,939)	1,553,610	(944,576)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(117,922)
Other comprehensive income (loss), net of tax	9,260
Ending balance at Jun. 30, 2021	527,719	441,369	1,848,201	(2,262,223)	1,435,688	(935,316)
Beginning balance at Mar. 31, 2021	490,565	441,369	1,836,958	(2,267,961)	1,441,225	(961,026)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	(5,537)				(5,537)
Other comprehensive income (loss), net of tax	25,710					25,710
Issuance of treasury stock for stock option exercises	2,154		(676)	2,830
Issuance of treasury stock for restricted stock units vesting	(529)		(3,212)	2,683
Deferred compensation	188		(37)	225
Share-based compensation	15,168		15,168
Ending balance at Jun. 30, 2021	527,719	441,369	1,848,201	(2,262,223)	1,435,688	(935,316)
Beginning balance at Dec. 31, 2021	1,568,849	441,369	1,832,144	(2,219,990)	2,456,597	(941,271)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	21,454				21,454
Other comprehensive income (loss), net of tax	12,061					12,061
Issuance of treasury stock for stock option exercises	13,935		(3,183)	17,118
Issuance of treasury stock for restricted stock units vesting	(17,555)		(43,523)	25,968
Share-based compensation	19,323		19,323
Adjustment of accumulated other comprehensive loss to retained earnings for available-for-sale securities	0				(2,801)	2,801
Ending balance at Mar. 31, 2022	1,618,067	441,369	1,804,761	(2,176,904)	2,475,250	(926,409)
Beginning balance at Dec. 31, 2021	1,568,849	441,369	1,832,144	(2,219,990)	2,456,597	(941,271)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	87,894
Other comprehensive income (loss), net of tax	25,322
Ending balance at Jun. 30, 2022	1,728,049	441,369	1,816,526	(2,158,388)	2,541,690	(913,148)
Beginning balance at Mar. 31, 2022	1,618,067	441,369	1,804,761	(2,176,904)	2,475,250	(926,409)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income (loss)	66,440				66,440
Other comprehensive income (loss), net of tax	13,261					13,261
Issuance of treasury stock for stock option exercises	12,347		(2,792)	15,139
Issuance of treasury stock for restricted stock units vesting	(763)		(3,997)	3,234
Deferred compensation	131		(12)	143
Share-based compensation	18,566		18,566
Ending balance at Jun. 30, 2022	$ 1,728,049	$ 441,369	$ 1,816,526	$ (2,158,388)	$ 2,541,690	$ (913,148)