Condensed Consolidated Statements of Earnings (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Apr. 05, 2014	Mar. 30, 2013
Income Statement [Abstract]
Net sales	$ 5,108,444	$ 4,550,772
Costs, expenses and other:
Cost of products sold	4,731,242	4,247,556
Marketing, administrative and other expenses	133,434	116,225
Equity in (earnings) losses of unconsolidated affiliates	(4,474)	1,172
Interest expense, net	40,741	32,491
Costs, expenses and other, total	4,900,943	4,397,444
Earnings before income taxes and noncontrolling interests	207,501	153,328
Provision for income taxes	77,805	42,600
Net earnings	129,696	110,728
Earnings attributable to noncontrolling interests	18,665	25,939
Net earnings attributable to Nucor stockholders	$ 111,031	$ 84,789
Net earnings per share:
Basic	$ 0.35	$ 0.26
Diluted	$ 0.35	$ 0.26
Average shares outstanding:
Basic	319,505	318,686
Diluted	319,768	318,842
Dividends declared per share	$ 0.3700	$ 0.3675