Condensed Consolidated Statements of Comprehensive Income (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Oct. 04, 2014	Sep. 28, 2013	Oct. 04, 2014	Sep. 28, 2013
Statement Of Comprehensive Income [Abstract]
Net earnings	$ 274,201	$ 178,115	$ 570,832	$ 395,113
Other comprehensive income (loss):
Net unrealized gain (loss) on hedging derivatives, net of income taxes of $100 and $0 for the third quarter of 2014 and 2013, respectively, and ($900) and $0 for the first nine months of 2014 and 2013, respectively	103	0	(1,530)	0
Reclassification adjustment for loss on settlement of hedging derivatives included in net income, net of income taxes of $100 and $0 for the third quarter of 2014 and 2013, respectively, and $200 and $0 for the first nine months of 2014 and 2013, respectively	197	0	430	0
Foreign currency translation (loss) gain, net of income taxes of $0 and $500 for the third quarter of 2014 and 2013, respectively, and ($400) and $300 for the first nine months of 2014 and 2013, respectively	(81,689)	31,879	(93,321)	(34,216)
Net current-period other comprehensive (loss) income	(81,389)	31,879	(94,421)	(34,216)
Comprehensive income	192,812	209,994	476,411	360,897
Comprehensive income attributable to noncontrolling interests	(28,754)	(30,518)	(67,313)	(77,582)
Comprehensive income attributable to Nucor stockholders	$ 164,058	$ 179,476	$ 409,098	$ 283,315