Condensed Consolidated Statements of Earnings - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Apr. 01, 2017	Apr. 02, 2016
Income Statement [Abstract]
Net sales	$ 4,815,179	$ 3,715,576
Costs, expenses and other:
Cost of products sold	4,054,929	3,400,591
Marketing, administrative and other expenses	176,426	109,745
Equity in earnings of unconsolidated affiliates	(8,756)	(9,245)
Interest expense, net	43,605	44,922
Costs, expenses and other, total	4,266,204	3,546,013
Earnings before income taxes and noncontrolling interests	548,975	169,563
Provision for income taxes	171,327	47,066
Net earnings	377,648	122,497
Earnings attributable to noncontrolling interests	20,749	34,932
Net earnings attributable to Nucor stockholders	$ 356,899	$ 87,565
Net earnings per share:
Basic	$ 1.11	$ 0.27
Diluted	$ 1.11	$ 0.27
Average shares outstanding:
Basic	320,224	319,240
Diluted	321,146	319,294
Dividends declared per share	$ 0.3775	$ 0.3750