Consolidated Statements of Changes in Stockholders' Equity - USD ($) $ in Thousands	Total	Common Stock Voting [Member]	Additional Paid-In Capital [Member]	Treasury Stock - Common Stock Voting [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Loss [Member]
Beginning Balance at Dec. 31, 2020	$ 955,061	$ 123	$ 329,742	$ (169,523)	$ 799,369	$ (4,650)
Net income	80,457				80,457
Cumulative translation adjustment and foreign currency exchange hedge, net of tax	(1,932)					(1,932)
Stock-based compensation	7,424		7,424
Exercise of stock options	244		244
Withholding tax payments on restricted stock vesting and stock option exercises	(27,422)		(27,422)
Repurchases of common stock	(520)			(520)
Cash dividend on common stock	(25,079)				(25,079)
Ending Balance at Mar. 31, 2021	988,233	123	309,988	(170,043)	854,747	(6,582)
Beginning Balance at Dec. 31, 2020	955,061	123	329,742	(169,523)	799,369	(4,650)
Net income	147,745
Cumulative translation adjustment and foreign currency exchange hedge, net of tax	(794)
Ending Balance at Jun. 30, 2021	1,021,860	123	313,683	(183,479)	896,977	(5,444)
Beginning Balance at Mar. 31, 2021	988,233	123	309,988	(170,043)	854,747	(6,582)
Net income	67,288				67,288
Cumulative translation adjustment and foreign currency exchange hedge, net of tax	1,138					1,138
Stock-based compensation	6,134		6,134
Exercise of stock options	4,421		4,421
Withholding tax payments on restricted stock vesting and stock option exercises	(6,860)		(6,860)
Repurchases of common stock	(13,436)			(13,436)
Cash dividend on common stock	(25,058)				(25,058)
Ending Balance at Jun. 30, 2021	1,021,860	123	313,683	(183,479)	896,977	(5,444)
Beginning Balance at Dec. 31, 2021	1,041,309	123	330,262	(232,712)	956,966	(13,330)
Net income	64,769				64,769
Cumulative translation adjustment and foreign currency exchange hedge, net of tax	(5,051)					(5,051)
Stock-based compensation	8,099		8,099
Exercise of stock options	50		50
Withholding tax payments on restricted stock vesting and stock option exercises	(20,292)		(20,292)
Repurchases of common stock	(38,800)			(38,800)
Cash dividend on common stock	(26,543)				(26,543)
Ending Balance at Mar. 31, 2022	1,023,541	123	318,119	(271,512)	995,192	(18,381)
Beginning Balance at Dec. 31, 2021	1,041,309	123	330,262	(232,712)	956,966	(13,330)
Net income	131,691
Cumulative translation adjustment and foreign currency exchange hedge, net of tax	(26,509)
Ending Balance at Jun. 30, 2022	1,000,802	123	325,047	(320,252)	1,035,723	(39,839)
Beginning Balance at Mar. 31, 2022	1,023,541	123	318,119	(271,512)	995,192	(18,381)
Net income	66,922				66,922
Cumulative translation adjustment and foreign currency exchange hedge, net of tax	(21,458)					(21,458)
Stock-based compensation	6,503		6,503
Exercise of stock options	86		86
Withholding tax payments on restricted stock vesting and stock option exercises	339		339
Repurchases of common stock	(48,740)			(48,740)
Cash dividend on common stock	(26,391)				(26,391)
Ending Balance at Jun. 30, 2022	$ 1,000,802	$ 123	$ 325,047	$ (320,252)	$ 1,035,723	$ (39,839)