CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (Unaudited) - USD ($) $ in Thousands		Total	Common Stock Member	Additional Paid In Capital Member	Retained Earnings Member	Accumulated Other Comprehensive Loss Member	Treasury Stock Member
Beginning Balance at Dec. 31, 2020			$ 49,187	$ 122,535	$ 2,670,328	$ (310,856)	$ (743,620)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings		$ 120,877			120,877
Other Comprehensive Income (Loss), Net of Tax		13,325				13,325
Dividends paid					(14,321)
Restricted stock				(9,007)			9,007
Employee stock purchase plan				411			4,508
Other				(597)			597
Share-based compensation				6,604			121
Repurchases of common stock	[1]						(24,395)
Ending Balance at Jun. 30, 2021			49,187	119,946	2,776,884	(297,531)	(753,782)
Beginning Balance at Dec. 31, 2020			49,187	122,535	2,670,328	(310,856)	(743,620)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Other Comprehensive Income (Loss), Net of Tax		120,391
Ending Balance at Dec. 31, 2021		1,826,490	49,187	127,104	2,908,827	(190,465)	(1,068,163)
Beginning Balance at Mar. 31, 2021			49,187	119,172	2,722,829	(309,216)	(743,808)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings		61,408			61,408
Other Comprehensive Income (Loss), Net of Tax		11,685				11,685
Dividends paid					(7,353)
Restricted stock				(2,600)			2,600
Share-based compensation				3,374			24
Repurchases of common stock	[1]						(12,598)
Ending Balance at Jun. 30, 2021			49,187	119,946	2,776,884	(297,531)	(753,782)
Beginning Balance at Dec. 31, 2021		1,826,490	49,187	127,104	2,908,827	(190,465)	(1,068,163)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings		111,557			111,557
Other Comprehensive Income (Loss), Net of Tax		(37,407)				(37,407)
Dividends paid					(14,220)
Restricted stock				(8,523)			8,523
Employee stock purchase plan				814			4,470
Other				(506)			506
Share-based compensation				7,427			153
Repurchases of common stock							(31,645)
Ending Balance at Jun. 30, 2022		1,867,639	49,187	126,316	3,006,164	(227,872)	(1,086,156)
Beginning Balance at Mar. 31, 2022			49,187	122,603	2,942,580	(191,524)	(1,073,426)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net earnings		70,872			70,872
Other Comprehensive Income (Loss), Net of Tax		(36,348)				(36,348)
Dividends paid					(7,288)
Share-based compensation				3,713			58
Repurchases of common stock							(12,788)
Ending Balance at Jun. 30, 2022		$ 1,867,639	$ 49,187	$ 126,316	$ 3,006,164	$ (227,872)	$ (1,086,156)

[1] For the three and six months ended June 30, 2022, the Corporation repurchased approximately 0.1 million and 0.2 million shares of its common stock, respectively. For the three and six months ended June 30, 2021, the Corporation repurchased approximately 0.1 million and 0.2 million shares of its common stock, respectively.