Basis of Interim Presentation - Schedule of Adjustments to Condensed Consolidated Statement of Earnings (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Apr. 01, 2017	Apr. 02, 2016
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cost of products sold	$ 4,054,929	$ 3,400,591
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
As Originally Reported [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cost of products sold		$ 3,428,628
Provision for income taxes		37,065
Net earnings		104,461
Earnings attributable to noncontrolling interests		33,707
Net earnings attributable to Nucor stockholders		$ 70,754
Net earnings per share:
Basic		$ 0.22
Diluted		$ 0.22
Effect of Change [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Cost of products sold		$ (28,037)
Provision for income taxes		10,001
Net earnings		18,036
Earnings attributable to noncontrolling interests		1,225
Net earnings attributable to Nucor stockholders		$ 16,811
Net earnings per share:
Basic		$ 0.05
Diluted		$ 0.05