Condensed Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($) $ in Thousands	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Treasury Stock [Member]	Total
Balance at Dec. 31, 2020	$ 1,671	$ 408,244	$ 4,984,739	$ (2,794,516)	$ 2,600,138
Net earnings	0	0	518,597	0	518,597
Common Stock, Dividends, Per Share, Cash Paid	0	0	(92,891)	0	(92,891)
Purchase of treasury shares	0	0	0	(136,917)	(136,917)
Share-based compensation	0	47,411	0	0	47,411
Restricted share issuances, net of stock repurchased for payroll taxes and other	0	(10,747)	0	(3,363)	(14,110)
Balance at Sep. 30, 2021	1,671	444,908	5,410,445	(2,934,796)	2,922,228
Balance at Jun. 30, 2021	1,671	436,736	5,242,206	(2,881,585)	2,799,028
Net earnings	0	0	199,829	0	199,829
Common Stock, Dividends, Per Share, Cash Paid	0	0	(31,590)	0	(31,590)
Purchase of treasury shares	0	0	0	(50,336)	(50,336)
Share-based compensation	0	15,946	0	0	15,946
Restricted share issuances, net of stock repurchased for payroll taxes and other	0	(7,774)	0	(2,875)	(10,649)
Balance at Sep. 30, 2021	1,671	444,908	5,410,445	(2,934,796)	2,922,228
Balance at Dec. 31, 2021	1,671	448,217	5,621,103	(2,953,175)	3,117,816
Net earnings	0	0	768,048	0	768,048
Common Stock, Dividends, Per Share, Cash Paid	0	0	(125,228)	0	(125,228)
Purchase of treasury shares	0	0	0	(300,030)	(300,030)
Share-based compensation	0	59,737	0	0	59,737
Restricted share issuances, net of stock repurchased for payroll taxes and other	0	(10,498)	0	(4,736)	(15,234)
Balance at Sep. 30, 2022	1,671	497,456	6,263,923	(3,257,941)	3,505,109
Balance at Jun. 30, 2022	1,671	483,109	6,036,095	(3,196,011)	3,324,864
Net earnings	0	0	269,382	0	269,382
Common Stock, Dividends, Per Share, Cash Paid	0	0	(41,554)	0	(41,554)
Purchase of treasury shares	0	0	0	(60,690)	(60,690)
Share-based compensation	0	20,153	0	0	20,153
Restricted share issuances, net of stock repurchased for payroll taxes and other	0	(5,806)	0	(1,240)	(7,046)
Balance at Sep. 30, 2022	$ 1,671	$ 497,456	$ 6,263,923	$ (3,257,941)	$ 3,505,109