Consolidated Statements of Stockholders' Equity - USD ($) $ in Thousands	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	AOCI Attributable to Parent [Member]	Treasury Stock [Member]	Total
Balances at Dec. 31, 2018	$ 1,671	$ 340,457	$ 4,188,435	$ 0	$ (2,429,179)	$ 2,101,384
Net earnings	0	0	516,320		0	516,320
Cash dividend declared and paid	0	0	(111,817)		0	(111,817)
Purchase of treasury shares	0	0	0		(275,657)	(275,657)
Share-based compensation	0	53,324	0		0	53,324
Restricted share issuances, net of stock repurchased for payroll taxes and other	0	(19,732)	0		3,207	(16,525)
Balances at Dec. 31, 2019	1,671	374,049	4,592,938	0	(2,701,629)	2,267,029
Net earnings	0	0	506,035		0	506,035
Cash dividend declared and paid	0	0	(114,234)		0	(114,234)
Purchase of treasury shares	0	0	0		(92,548)	(92,548)
Share-based compensation	0	60,698	0		0	60,698
Restricted share issuances, net of stock repurchased for payroll taxes and other	0	(26,503)	0		(339)	(26,842)
Balances at Dec. 31, 2020	1,671	408,244	4,984,739	0	(2,794,516)	2,600,138
Net earnings	0	0	760,806		0	760,806
Cash dividend declared and paid	0	0	(124,442)		0	(124,442)
Purchase of treasury shares	0	0	0		(151,720)	(151,720)
Share-based compensation	0	61,505	0		0	61,505
Restricted share issuances, net of stock repurchased for payroll taxes and other	0	(21,532)	0		(6,939)	(28,471)
Balances at Dec. 31, 2021	$ 1,671	$ 448,217	$ 5,621,103	$ 0	$ (2,953,175)	$ 3,117,816