Condensed Consolidated Statements of Earnings - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 03, 2021	Jul. 04, 2020	Jul. 03, 2021	Jul. 04, 2020
Income Statement [Abstract]
Net sales	$ 8,789,164	$ 4,327,306	$ 15,806,304	$ 9,951,643
Costs, expenses and other:
Cost of products sold	6,315,661	3,949,347	11,710,364	8,944,416
Marketing, administrative and other expenses	387,070	142,017	678,194	295,409
Equity in (earnings) losses of unconsolidated affiliates	(19,403)	14,078	(32,642)	14,901
Losses on assets	44,308	5,000	50,970	292,846
Interest expense, net	35,780	35,807	75,424	76,717
Costs, expenses and other, total	6,763,416	4,146,249	12,482,310	9,624,289
Earnings before income taxes and noncontrolling interests	2,025,748	181,057	3,323,994	327,354
Provision for income taxes	454,289	47,904	765,021	139,822
Net earnings	1,571,459	133,153	2,558,973	187,532
Earnings attributable to noncontrolling interests	64,591	24,272	109,673	58,320
Net earnings attributable to Nucor stockholders	$ 1,506,868	$ 108,881	$ 2,449,300	$ 129,212
Net earnings per share:
Basic	$ 5.05	$ 0.36	$ 8.14	$ 0.42
Diluted	$ 5.04	$ 0.36	$ 8.13	$ 0.42
Average shares outstanding:
Basic	296,817	302,921	299,359	302,915
Diluted	297,529	302,933	299,738	302,932